I mean wouldn't any argument against a QB having a W-L record also apply against a QB having a completion percentage, or stats for ints or TDs or sacks? I've yet to see the QB who blocks for himself, and I've yet to see the QB who lines up with no O-Lineman and successfully completes a high percentage of his throws without any blocks whatsoever. I've yet to see the QB who consistently throws to themselves, blocks for themselves afterwards, and runs for their own yards after the catch. I've yet to see the QB who lines up alone against an opposing 11 and moves the ball whatsoever. And despite the tales of Manning, I've yet to see the QB who designs all their own plays and coaches all positions. Until I've seen those things, isn't every single statistic a team statistic, with influences beyond the control of the QB involved in its creation?
All a QB can do is their best to put their team in the right position - in terms of getting them in the right plays, in terms of putting the ball in the right spot, in terms of winning the game. It's up to the rest of the team to execute, to catch that ball, to win. A great QB will see their team be successful, in terms of catches, yards, TDs, and wins, more often than a terrible QB. A QB can play great and still lose or play terribly and still win, a perfectly thrown ball can be needlessly bobbled by a teammate and become an interception instead of a TD. But looking at the whole of things is still informative about the quality of the QB, because over a large enough sample size, the impact of the QB play shines through regardless of mitigating factors. That same case applies equally, regardless of whether we're talking about recording completion percentage or wins, does it not?
:LOL: 
