You will recall, Dear Reader, that
I addressed not long ago the question of whether or not the American League should have an inherent structural advantage over the National League due to the existence of the DH. I concluded that it should not and speculated that one of the reasons that the AL is dominating the NL in interleague play could be simply that the AL has more resources at its disposal.
This appears to be the case, as Tom Tango notes
here:
The effect is that the average NL payroll for those five years is 74MM per team, and the average AL payroll is 84MM. Each AL team has 10MM more dollars of talent than the NL teams.
Does this explain all of the effect? I don't know, but it certainly goes a long, long way.