What is this "DH" you guys speak of? Pitchers don't hit in the AL? You don't say!
But seriously, I don't think the difference is as drastic as people think. I think pitchers largely pitch to their skill level.
How many points higher do you think the #9 hitters in the AL hit than the #9 hitters in the NL? I bet its less than you think.
Its just silly hearing how every guy who switches over "should do better/worse" in his new league, as if its a given.
I'm trying to find a more recent article but it definitely exists. It's maybe not as significant as people consider but it absolutely exists.
From 2000 through 2005, 57 starting pitchers (those with at least 20 starts that season) switched leagues the next year — 29 to the N.L. from the A.L. and 28 in the other direction. Their statistics moved with them: Combined E.R.A.s for the new National Leaguers decreased to 3.94 from 4.79, or 0.85 of a run, while their counterparts’ increased to 4.64 from 3.94, a move of 0.70.
Of the 29 pitchers moving to the N.L. from the A.L., their E.R.A.+ figures increased to 110 (10 percent above league average) from 97 (just below average). This smaller shift than in E.R.A. is nonetheless more significant: It indicates that starters of equal caliber are more successful in the less suffocating National League.
This almost certainly helped with last season’s emergence of Bronson Arroyo, traded to Cincinnati from Boston; and Chris Young, who went to San Diego from Texas. It also provides fuel to the recent argument that the N.L. lags behind the A.L. in the overall level of talent. Weaker competition results in better relative performance.
Pitchers found moving to the A.L. from the N.L. correspondingly unpleasant — the E.R.A.+ scores of the 28 pitchers decreased to 100 from 113, or to absolute average from healthily above. (The fact that the two groups moved 13 percentage points in opposite directions was purely coincidental.) A fair interpretation, then, is that moving to the A.L. is such a challenge that pitchers, at least temporarily, regress. Take the case of Boston’s Josh Beckett, whose 5.01 E.R.A. rose faster than the homers he allowed.
http://www.nytimes.com/2007/01/14/sports/baseball/14score.html
Again, still looking for a more recent article...