Walkers Career Home Road Splits



Jim Rice Home Road Splits




Duke Snider (Walkers Closet BB-Ref comp)

By the way, I think the bigger knock on Walker was how many games he missed due to injuries. Only over 150 games once, only 4 seasons over 140 games.

Can't control where he played?

I thought Walker chose Colorado as a free agent. Not that playing in Colorado should disqualify him.

I'm as big a Walker fan as anyone, but I can't say with certainty that I think he should be in. He does have a point about Martinez though. Edgar was undoubtedly a better hitter, but Walker was much, much better at everything else.

Shoewizard is right - not including his cup of coffee in '89, he only averaged 123 games a year for his career. That makes induction pretty tough if you're not an all-world hitter.

You can’t always pick where you go or what happens.

Transactions

November 14, 1984: Signed by the Montreal Expos as an amateur free agent.
October 24, 1994: Granted Free Agency.
April 8, 1995: Signed as a Free Agent with the Colorado Rockies.

Shoewizard is right - not including his cup of coffee in '89, he only averaged 123 games a year for his career. That makes induction pretty tough if you're not an all-world hitter.

I pointed out in another thread, Walker, like Barry Larkin, had the misfortune of being healthy during the strike years and injured during full years. He played 103 of 114 in 1994, and 131 of 144 in 1995. Still no iron man for sure, but the strikes make him look worse than he was.

October 24, 1994: Granted Free Agency.
April 8, 1995: Signed as a Free Agent with the Colorado Rockies.

He obviously leapt at the chance.

Duke Snider (Walkers Closet BB-Ref comp)


When I first read this word (as spelled), I thought that Sean had some double-secret new fangled comp thingy.

I don’t think it bothers me a lot.

The following comments don't exactly match up, do they?

Walker is right there on the border with Dale Murphy and Edgar. No travesty if any get in either.

He obviously leapt at the chance.

I don't think there was any leaping going on league-wide between Oct. 24 and April 8.

Adjusted comps for Larry Walker, centered on him in terms of OPS+ and PAs, ranked by WAR Fielding Runs, with a couple of other items of info.



The search was 1893-present, so it chops off the first couple of years of the careers of HOFers Kelley and Burkett. (As well as the Negro League years of Minoso, of course.) Basically the list consists of a lot of great-hitting LFs who didn't have long careers, the better players on it being the better fielders in RF and CF (Walker, Edmonds, Snider). Reggie Smith is a very close comp in a lot of ways. I agree with Taussig Avenger, this is such a close call – I hope Walker will be remembered for an outstanding and unusual career no matter what Halls he makes.

Edgar's split

Split...PA....HR..RBI...BA..OBP..SLG..OPS..TB..BAbip
Home 4282 149 636 .311 .423 .517 .940 1815 .337
Away 4390 160 625 .312 .412 .514 .926 1903 .334

I pointed out in another thread, Walker, like Barry Larkin, had the misfortune of being healthy during the strike years and injured during full years. He played 103 of 114 in 1994, and 131 of 144 in 1995. Still no iron man for sure, but the strikes make him look worse than he was.

Good point about the strike years distorting the view of Walkers durability somewhat. But Larkin, for all the dings he got due to injury time, looks like Lou Gehrig compared to Walker

4 seasons over 150 games, 7 seasons over 140 games, (and 110 out 114 in 94 and 131 out of 144 in 95 as well)

Split...PA....HR..RBI...BA..OBP..SLG..OPS..TB..BAbip
Home 4282 149 636 .311 .423 .517 .940 1815 .337
Away 4390 160 625 .312 .412 .514 .926 1903 .334

Yea, that unusual balance is because the Kingdome was really close to a league average park in park factors, and then he finished the last 6 years in Safeco.

Of course if Edgar had played in Coors field, simple math tells us it's extremely likely he would have had a massive gulf between his home and road splits, just like Walkers.

Good point about the strike years distorting the view of Walkers durability somewhat. But Larkin, for all the dings he got due to injury time, looks like Lou Gehrig compared to Walker

Agree. But it does point out how is important to know more about a player than just his BBREF stat lines. Walker, Larkin, Raines, among others, get dinged for playing time which looks worse than it is due to strikes and other labor issues. " McGriff never hit more than 37 HRs." True, but he hit 34 in 113 games in 1994. " Maddux won 20 games only twice." Well, true, but he would have had 2 more in 1994 and 1995 given a full season. "Sosa came out of nowhere to hit 66 HR in 1998." Well, he had a league leading 40 in mid Aug 1996 when he was struck on the wrist and out for the season. "Imagine the stat line Bagwell could have had in 1994 if not for the strike." Well, no, Bags was out for the season a few days before the strike. In his case, the strike helps his HOF chances, as he probably wouldn't have had the MVP otherwise. And so on.

Oddly, Larry is comparable to Duke Snider in another way. Playing in a ballpark that favored lefty hitting, Duke found himself for several years as the only lefty bat of any consequence in his lineup (Gilliam was a switch hitter, and the other lefties were, um, "not of significance." Duke took heat for this for years, and it may have affected his HoF candidacy. - Brock Hanke

How did Duke Snider get the nickname Duke?

Edgar Martinez [only played 592 of his 2,055 career games in the field] and he’s getting twice as many votes as me [36.5 per cent to Walker’s 22.9 per cent]. Is Edgar Martinez twice the better player than me?

Yes. Your vote total exactly correlates to how good a player you are.

"Snub" is such a weird word for a person who just passed his second year on the ballot for the ############# BASEBALL HALL OF FAME.

I agree - the BBWAA aren't intentionally trying to insult Walker. I would bet most writers knew he was a hellofa ballplayer - Coors field or no.

One could argue that some writers are "snubbing" guys like McGwire.

Are you she—-in me?

I'm not familiar with this expletive. Unless it's three syllables long, rather than two as I'm assuming.

Are you sheepin' me??

I think Coors Field might help Walker as much as it hurts him. Without it, there's virtually no black ink, he hits .298 lifetime or something, the counting stats are even less impressive, he's down to only a couple of 100 RBI seasons, etc. His value would be what it was, but the record wouldn't have the superficial "Hall of Fame look" for the voters.

Edgar Martinez [only played 592 of his 2,055 career games in the field] and he’s getting twice as many votes as me [36.5 per cent to Walker’s 22.9 per cent]. Is Edgar Martinez twice the better player than me?

Geez Larry, you should be honored that the voters consider you 130 times better than Javy Lopez.

Raines, 21-33: 7971 PA, 129 OPS+, 59 WAR, 56 oWAR
Walker, career: 8030 PA, 140 OPS+, 67 WAR, 58 oWAR

Raines added another solid 2400 PA -- 107 OPS+, 6 WAR, 9 oWAR -- which is balanced against Walker's superior defense.

I think the fixation on in-season playing time is unwarranted. For example, Larkin had over 9000 PA while Santo had about 9400. All that means is that Santo provided more value over fewer years while Larkin provided value over more years. Naturally, Santo's "short" career was held against him and Larkin's lack of "durability" was held against him (though obviously not too strongly).

Career PA are career PA and if they're roughly equal between two players, I don't think it matters one bit how many years they compiled them over. Any point to in-season durability is more easily handled by placing a greater value on peak.

Now Walker had a short career by HoF standards. So did Edgar but it is 600 more PA than Walker. Edgar was also not a paragon of in-season durability (but probably better than Walker) but that's not held against him around here.

How did Duke Snider get the nickname Duke?

apparently his father gave him that nickname at age 5 and neither Duke nor his father could ever remember why

Walker seems thoughtful and comfortable with nuance, which is refreshing.

Are you she—-in me?

I went with, "Are you Sheboygan me?" I could see putting an "i" in for that schwa.

He obviously leapt at the chance.

And tore his ACL.

Walker likely suffers from not having any outstanding attributes--he was just really good at everything. He was a very good defender (both range and arm) and baserunner (SB/CS and on BIP) by both reputation and stats, hit for average, hit for power, and took walks.

And I think he's using "snub" the way it's commonly used when talking about awards voting or all-star selections. It's generally not an accusation of intentional insult.

Of course if Edgar had played in Coors field, simple math tells us it's extremely likely he would have had a massive gulf between his home and road splits, just like Walkers.

..and would have had a better-than-decent shot of hitting .400.

Of course if Edgar had played in Coors field, simple math tells us it's extremely likely he would have had a massive gulf between his home and road splits, just like Walkers.

while maintaining his better road OPS & BAbip.

while maintaining his better road OPS & BAbip.

Nope.

If you take the best hitters park in the league out of your road games, and replace it with an average, or much worse than average park like Safeco, your road numbers are going to be affected.

That's why we ignore splits and use park adjusted stats like OPS+in comparisons like this. Edgar was still better, but not by a lot, 147-140.

Is that really the only reason we don't assume that a player's road stats will remain the same when his home park changes? Because the road stats will now include Park A instead of Park B? Because that doesn't seem relevant, as Edgar Martinez played all of 5 games in Coors Field.

apparently his father gave him that nickname at age 5 and neither Duke nor his father could ever remember why

IIRC, it that his dad walked him to his first day of kindergarten, worried that his boy would cling to him, or start bawling when dad went to leave. But instead, his son strutted around like royalty, so dad nicknamed him Duke.

If you take the best hitters park in the league out of your road games, and replace it with an average, or much worse than average park like Safeco, your road numbers are going to be affected.

Edgar's Safeco numbers (879 OPS, .326 BAbip in 1581 PA) are better than Walker's road numbers (.865/.301)

Is that really the only reason we don't assume that a player's road stats will remain the same when his home park changes? Because the road stats will now include Park A instead of Park B? Because that doesn't seem relevant, as Edgar Martinez played all of 5 games in Coors Field.

I've heard the argument made that hitters that play in Coors get used to hitting in Coors, and thus hit more poorly in other parks than their context-neutral numbers would indicate. In particular, because breaking balls don't snap as much in Coors, they can't hit them elsewhere. I seem to recall this is backed up by something quantitative... compare hitting in X constant set of other NL parks for hitters pre-, during, and post-Coors, or something like that... but I don't recall any details.

[1] The .385 BAbip in Coors Fld clearly drives his home split. Olympic Stadium didn't exactly do that.

Larry Walker Career Batting Splits by Ballpark, sorted by PA, from BB-REF

            Split   G  GS PA    AB   R   H  2B 3B  HR RBI SB CS  BB  SO   BA  OBP   SLG   OPS   TB GDP HBP SH SF IBB ROE BAbip tOPS+
       COL-Coors Fld 597 555 2501 2136 555 814 178 31 154 521 74 16 286 291 .381 .462  .710 1.172 1516  56  55  0 24  40  23  .385   141
    MON-Stade Olymp. 350 323 1369 1194 204 350  84  8  56 211 49 19 138 238 .293 .373  .518  .890  618  23  21  4 12  28   9  .322    85
      STL-Busch Stad 148 131  558  476  96 140  29  1  28  87  4  9  64  79 .294 .391  .536  .926  255  16  14  0  4   5   3  .300    93

     SDP-Qualcomm St  78  71  322  281  51  77  13  1  23  59  7  2  34  49 .274 .354  .573  .927  161   4   3  0  4   4   5  .254    90
     CHC-Wrigley Fld  70  66  304  243  46  80  14  2  12  51 11  2  54  28 .329 .451  .551 1.002  134   4   3  0  4   7   4  .329   110
     LAD-Dodger Stad  77  69  302  262  46  72  10  2  10  34  9  5  33  69 .275 .365  .443  .808  116   6   5  1  1   4   1  .337    70
       NYM-Shea Stad  70  62  267  234  25  51  16  0   8  34  8  3  25  54 .218 .296  .389  .685   91   2   3  0  5   0   3  .243    43
    PHI-VeteransStad  66  58  258  220  37  58  14  1   8  29  9  1  32  45 .264 .364  .445  .810   98   4   4  0  2   3   4  .296    70
    PIT-3 Rivers Std  61  58  251  229  33  61  13  1  10  29  7  5  16  46 .266 .323  .463  .786  106   5   4  0  2   5   1  .291    63
     CIN-Cinergy Fld  59  57  250  222  41  65  15  1  16  48  5  2  26  46 .293 .368  .586  .954  130   5   1  0  1   1   1  .304    96
       SFG-3Com Park  54  51  213  183  25  51   7  1   8  24  9  4  24  34 .279 .373  .459  .832   84   6   4  1  1   2   3  .303    74
    FLA-ProPlayerStd  45  45  194  161  23  46   6  2   8  25  6  2  31  29 .286 .402  .497  .899   80   3   1  0  1   7   2  .304    88
    ARI-Bank One Bpk  41  39  170  140  27  49  11  1   5  23  2  2  27  26 .350 .465  .550 1.015   77   0   3  0  0   2   1  .404   114
       HOU-Astrodome  43  39  162  143  23  31  10  0   1   9  8  1  15  35 .217 .304  .308  .612   44   4   3  1  0   0   1  .280    30
      ATL-Atl-Fulton  35  34  144  132  18  43   6  1   7  23  7  1  12  24 .326 .382  .545  .927   72   0   0  0  0   0   1  .356    92
      ATL-Turner Fld  28  26  118  101  25  32   6  2   7  22  4  0  14  16 .317 .415  .624 1.039   63   1   3  0  0   2   2  .321   114
    SFG-PacBell Park  33  29  117   96  10  20   4  1   2  11  2  0  20  30 .208 .350  .333  .684   32   2   1  0  0   0   3  .281    46
    HOU-MinuteMaidPk  19  19   76   71   9  15   3  4   2   8  1  0   5  23 .211 .263  .451  .714   32   1   0  0  0   0   0  .283    46
          PIT-PNC Pk  19  16   76   67   6  21   6  1   0   8  1  0   8   9 .313 .382  .433  .814   29   1   0  0  1   2   1  .356    72
       MIL-Miller Pk  17  14   64   56   7  13   3  0   4   9  0  1   7  17 .232 .328  .500  .828   28   1   1  0  0   2   1  .257    70
     OAK-Oakland Col   8   7   32   25   6   8   1  0   4   5  1  0   6   5 .320 .469  .840 1.309   21   0   1  0  0   1   0  .250   166
    TEX-Bp Arlington   7   7   30   27   3   5   4  0   0   2  0  0   2   5 .185 .267  .333  .600    9   2   1  0  0   1   1  .227    26
    COL-MileHigh Std   7   6   30   27   7   9   3  1   1   7  1  0   2   4 .333 .367  .630  .996   17   2   0  0  1   0   0  .348   103
    ANA-Anaheim Stad   8   7   29   22   2   3   0  0   1   2  3  0   5   3 .136 .345  .273  .618    6   0   2  0  0   1   0  .111    35
    CIN-GreatAmer BP   7   6   27   24   2   6   2  0   0   3  0  0   3   5 .250 .333  .333  .667    8   2   0  0  0   0   0  .316    42
     MIL-County Stad   8   6   27   23   5   7   2  0   0   3  1  0   3   4 .304 .407  .391  .799    9   2   1  0  0   0   0  .368    71
         TOR-SkyDome   6   5   21   17   2   3   0  0   2   4  0  0   3   4 .176 .333  .529  .863    9   0   1  0  0   0   0  .091    77
      CLE-Jacobs Fld   3   3   15   12   4   6   1  0   3   5  0  0   3   1 .500 .600 1.333 1.933   16   0   0  0  0   0   0  .375   286
       BOS-Fenway Pk   3   3   13    9   2   3   3  0   0   3  0  0   3   2 .333 .462  .667 1.128    6   0   0  0  1   0   0  .375   134
       MIN-Metrodome   3   3   13   12   1   3   0  0   1   3  0  0   1   2 .250 .308  .500  .808    6   0   0  0  0   0   0  .222    66
      SEA-Safeco Fld   3   3   13   10   3   6   2  0   1   1  0  0   2   0 .600 .692 1.100 1.792   11   1   1  0  0   0   0  .556   268
     DET-Comerica Pk   3   3   12   11   3   3   1  0   0   0  0  1   1   1 .273 .333  .364  .697    4   0   0  0  0   0   0  .300    48
    KCR-KauffmanStad   3   3   12   10   4   3   2  0   1   4  0  0   1   1 .300 .417  .800 1.217    8   0   1  0  0   0   0  .250   146
        SDP-PetCo Pk   3   3   12    8   1   2   2  0   0   2  1  0   2   3 .250 .417  .500  .917    4   0   1  0  1   0   0  .333    93
    PHI-CitizensBank   2   2    9    8   2   0   0  0   0   0  0  0   1   3 .000 .111  .000  .111    0   0   0  0  0   0   1  .000   -72
    TBD-TropicanaFld   2   2    9    6   1   2   0  0   0   1  0  0   3   0 .333 .556  .333  .889    2   0   0  0  0   0   1  .333    98
        SEA-Kingdome   1   1    6    6   0   2   0  0   0   1  0  0   0   0 .333 .333  .333  .667    2   0   0  0  0   0   0  .333    42
        WSN-RFK Stad   1   1    4    3   0   0   0  0   0   0  0  0   1   0 .000 .250  .000  .250    0   0   0  0  0   0   0  .000   -38

[1] Snider's Ebbets Field tOPS+ was only 116, and Rice's Fenway Park tOPS+ was only 115, as compared to Walker's Coors Field tOPS+ split of 141.

For everyone that posts home/road splits.....remember that most players perform better at home than on the road. I know some amateur data people think road is some kind of "true" measure of talent. It is not.

If you take the best hitters park in the league out of your road games, and replace it with an average, or much worse than average park like Safeco, your road numbers are going to be affected.

That's why we ignore splits and use park adjusted stats like OPS+in comparisons like this. Edgar was still better, but not by a lot, 147-140.

This guy gets it. Not only that.....the majority of players are better at home than on the road....for all you amateur data people.

Danny Posted: January 20, 2012 at 02:35 PM (#4041395)

Walker likely suffers from not having any outstanding attributes--he was just really good at everything. He was a very good defender (both range and arm) and baserunner (SB/CS and on BIP) by both reputation and stats, hit for average, hit for power, and took walks.

- couldn't agree more

larry is one of the best fielders and baserunners i have ever had the pleasure of watching

it's tough for me to dismiss him as a coors field creation, partly because he was so good when he was with the cards at the end of his career, and because basically every guy who played at coors had HUGE home/away splits

for some reason guys who hit a lot but can't do anything else get a lot more credit than guys like larry walker. i suppose it's just because you don't have exactly perfect numbers for fielding and baserunning.

i think that larry walker is a HOF quality player who will be left out because he didn't have enough PA

That's why we ignore splits and use park adjusted stats like OPS+in comparisons like this. Edgar was still better, but not by a lot, 147-140.

OPS+ underrates Edgar in comparison to Walker because of his huge OBP.

The issue of durability is brought up a lot here and there's some merit to the argument that a guy who plays 120 games for 15 years hurts his teams more than a guy who plays 162 games for 11 despite both playing roughly the same number of games, particularly at star level. It's much easier to allocate your resources effectively with the latter than the former and therefore likely results in better results. How much this should matter is another story.

Now Walker did play a little more than Edgar which is in his favor and he certainly was much better on the basepaths and in the field, which is a huge plus in his favor. But he needs every bit of all of that, because he simply wasn't in Edgar's league as a hitter. Not many guys in the last 30 years have been.

Obviously the HOF is going to force voters to pick one or the other....Walker or Edgar.

I think the fixation on in-season playing time is unwarranted. For example, Larkin had over 9000 PA while Santo had about 9400. All that means is that Santo provided more value over fewer years while Larkin provided value over more years.

Hall of Value. Sounds like a place that sucks, actually.

For everyone that posts home/road splits.....remember that most players perform better at home than on the road. I know some amateur data people think road is some kind of "true" measure of talent. It is not.

Holy Captain Obvious. CONTEXT !!!!!!

The article discusses what ? How Walker's HOF case with the voters has been discounted because of Coors Field. I posted the splits to show how other Hall of Famers had similar home road splits, and in the end it didn't seem to hurt their case quite as much. Nobody said anything about measuring true talent. Try not to pontificate too much as if you are the only one who "gets it".

This guy gets it. Not only that.....the majority of players are better at home than on the road....for all you amateur data people.

Actually, you look at ALL of it. You don't just look at Park adjusted stats that are based on faulty park factors. People who have been paid to do this for a living get THAT.

Edgar's Safeco numbers (879 OPS, .326 BAbip in 1581 PA) are better than Walker's road numbers (.865/.301)

Yes, because Safeco was his home park, and because it probably wasn't harder to hit in Safeco as a home player than it was for Walker to hit in the collection of road parks he had to hit in as a visitor, and because Edgar was te better hitter.

Here is the easiest way I can put it. Players always since the beginning of time tend to hit better at home than on the road, by about 4-5% in aggregate IIRC. That means if they played in identical parks, same sizes, elevation, wind patterns, weather, etc. let's use 100 to represent league average hitting, just like we do to represent a league average park factor. In this league of identical parks, hitters would average 98 on the road, and 102 at home.

But parks aren't identical in the real world. Imagine you play in the best hitters park in the league, so good it averages around a 124 park factor. Since league wide park factors have to average out to 100, it means 15 other parks have to average a 98.5 to balance out your home park. So at home you hit in a park that is a 126+ with the standard 2% bump for home hitters, but on the road the average park is in a 96-97 range with the additional 2% handicap of hitting on the road. Of course you have a huge split, you have the easiest home park to hit in, and the 15 toughest road parks to hit in the entire league.

In fact, your road parks are likely just as tough, if not slightly tougher, to hit in than Safeco was for Edgar. Safeco averaged around a 95 during his tenure there, and with his 2 pt home advantage that works out to roughly 97.

Actually, you look at ALL of it. You don't just look at Park adjusted stats that are based on faulty park factors. People who have been paid to do this for a living get THAT.

The dirty little secret I think is park factors don't make total sense because of te influence of the quality of players who play there, parks with good home staffs or mediocre hitters seem to get more credit for run suppression than they deserve, and vica versa with strong offensive teams and weak staffs.

But it doesn't change the big picture in what I wrote. If you compare home vs. road stats for hitters in the leagues best offensive parks, their road stats will always suffer more than usual by being accumulated mostly in the leagues toughest parks to hit in.

Once again...the reason I posted the splits was to show that those splits should NOT be a disqualifying factor for Walker.


I think that if Walker had 1000 more PA's, the voters would see past the Coors field issue. From age 23-36 he played in just 81% of his teams games.

From 1995-2002, his Coors field peak, (late peak....age 28-35) he had a 150 OPS+. But he only managed to play in 77% of his teams games.....missed almost 40 games a year.

There was always a bit of a "what might have been" feeling to Walkers career. He just missed so many games.

I personally WOULD vote for Walker....but he is right on the edge. The missed time is a lot more problematic for me than Coors field.

This guy gets it. Not only that.....the majority of players are better at home than on the road....for all you amateur data people.

The derogatory use of 'amateur data people' coupled with the endorsement of OPS+ - which vastly underrates OBP, and should only be used for broad strokes - is precious. Well done.

[1] Snider's Ebbets Field tOPS+ was only 116, and Rice's Fenway Park tOPS+ was only 115, as compared to Walker's Coors Field tOPS+ split of 141.

Walker didn't play his entire home career at Coors; the move to Colorado coincided nicely with a large spike in overall league offense. If you adjust for that, his Montreal home split goes from .373/.518 OBP/SLG to .393/.570 - still not his Coors numbers, obviously, but it'd be a tOPS+ of 99 rather than 85. Or, if you make the same adjustment in reverse (putting his Colorado stats in the 1990-94 league context rather than 1995-03), the Coors number drops to 124.

Anyway, the point in post 1 was not that Walker didn't have a huge Coors split, which he did (as do all other Colorado hitters); it was that he didn't have an unusually huge home-road split. His career home tOPS+ was 120, which is not out of line with Snider and Rice at all. (Or Ron Santo's 118, or Carl Yastrzemski's 115, or Wade Boggs's 118, or Chuck Klein's 122, or probably any number of other people who played in hitters' parks.)

#45 That's because park adjustments are not intended to measure ability. They're intended to measure value in context -- not quite the same thing (though obviously highly related).

In measuring value we don't particularly care that Joe DiMaggio was not well suited for his park or that Sandy Koufax took such great advantage of his that he personally moved the park factors a couple of points.

We know how many runs a player created. We know the runs required to create a win in the league offensive context. We know how a park affects run scoring relative to other parks in the league.

So we know how much a player contributed to him team winning (+/- ~5 runs per 650 PAs for the better metrics. More like ~8-9 runs for OPS+)

And we don't adjust for ability for two primary reasons. Parks will affect different players differently. See for instance the Morris thread where we've been discussing the Polo Grounds. Both Mel Ott and Bill Terry were pretty good left-handed hitters who had plenty of time to adjust to the peculiarities of the Polo Grounds. Ott hit better at home, Terry on the road.

Realistically every park plays differently according not merely to handedness, but also to pull frequency, GB/FB tendencies. Peculiarities of visibility probably affect players unequally. Amount of foul ground might or might not -- don't really know (and when you start slicing the available data that fine you run into sample size issues)

The second issue is that i we don't really understand how changing parks will affect any given player. Dan and I have been discussing Colorado players moving to a new park for a long time -- basically as long as the Rockies have been around. A lot of them had huge home/road splits (larger than predicted by simple park factors)leading many people to assume that once they left Colorado they'd be useless. In fact what best predicted how well they'd play in their new home was not road stats, or weighted road stats but rather their overall numbers adjusted using the Colorado park factors.

In the time we've been discussing this, Dan has put in a ton of work on this issue. And has shaved maybe a run off the standard error on his projections.

EDIT: (added the bolded not)

#46 I'm not so sure. It's no accident that Walker won his MVP in a year when his road stats were sensational ( .346/.443/.733 -- and more HR on the road than at home)

In following the MVP discussions at the time it's pretty clear that the voters understood that Colorado was a really unusual place to hit. Rather that adjust for it by discounting the numbers, the voters basically ignored the Colorado part of the numbers. And I'm pretty sure that's what will continue to happen for a sizable portion of the BBWAA.