Notice I didn't say that college success is a guarantee for professional success. Rather, the point was that failing to win in college (as was the case for Tuel and Edwards) doesn't bode well for NFL success.
So, your Tebow argument is irrelevant, Peyton has played precisely the way he has in the pros as he did in college, with a monkey on his back, thanks for making my point for me. Joe Flacco won at Delaware, and Aaron Rodgers won at Cal. Again, what was the point in bringing them up? And we're talking about QB's here, Keuchly doesn't belong in the conversation.