Take Favre away from the Pack and you still have Ahman Green. Take Warner away from the Rams and you have Faulk. Take Faulk away and you still have Warner and a better than average Trung Canidate. But take Jeff Garcia away from the 49ers and you have...nobody. Yes, Terrell Owens is there and he is arguably the best wideout in the league, but without Garcia getting him the ball on a consistent basis and the high level of play Garcia brings to the QB position on a weekly basis, the 49ers are a sub-500 team at best. I just think that in general the others on the list have a better all around supporting cast and taking Garcia away from the 49ers makes them a worse team than say, taking Faulk or Favre away from their teams.
Also, one cannot overlook Curtis Martin of the Jets. He gets the job done week in and week out and without him chewing up yardage the Jets would be unable to control the clock and utilize their short passing game effectively. So Martin gets my vote for a close second to Garcia as MVP halfway through the season.