The gap is becoming the Grand Canyon.
According to "Baseball Prospectus" an AL player switching league's can expect to increase his average and OBP 10 points. His Slugging would increase 20 points.
AL pitcher's can expect their ERA to drop 0.25 after accounting for the DH.
AL teams would win an average of 10 more games if it could face NL teams. NL teams would have the opposite 10 game fate. (Yankees of 07 would have had 107 wins while the Mets would have had 87).
The "gap" is widening. AL teams spent 75 mil to the NL's 71 million in 2004. In 2007, it's 93 mil to 74 mil. (Actually this is good news for the cubs).
The Chicago White Sox, KC Royals and Toronto Blue Jays are the surprising culprit's in this salary increase.
Another major factor is the overall Bill Wirtz like stinginess of NL owners who have signifigantly more profitable franchises (NL's 19.9 mil profit to the AL's 12.7).
Even these stat monster's admit how much luck it takes to win in the playoff's and they blame the Cardinal's (would have been the 11th best team in the AL last year) for allowing the trend to continue and the gap to widen.
Source's: (Story in today's NY Times)
Nate Silver of Baseball Prospectus
Dan Rosenheck of the NY Times
Bill James of the Red Sox
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