In order to figure out which QB was better at helping his team win, you need to separate team performance from QB performance.
Wow I actually agree with BL on this one (this should send him for a loop - he won't know how to handle it LOL).
You can't just say a QB is great based upon the success of his team. Sure, he's part of that, but a team winning doesn't necessarily mean they have a great QB.
Which is better:
Quarterback A has average stats for a starting QB over five years and his team wins the Super Bowl every one of those five years; or
Quarterback B leads the league in many significant passing categories for each of five years and sets records in some of them, but his team never even makes it to a single Super Bowl during that span because the team itself just isn't that good.
I would take the second one hands down every time and it wouldn't even be close, but many of you would think the first guy is better just because his team won and he "lead" them there simply be being the QB.