As far as the Chicago game, Denver was very fortunate to be playing Caleb Hanie instead of Jay Cutler. There's no way to slide around this fact.
How do you figure? I'm guessing your assumption is that Chicago would've handily won that game if Cutler had been playing. That is certainly one possibility. They get off to an early 14-0 or 21-3 lead, Denver never gets going offensively, and Chicago wins going away, sort of like that earlier Detroit game.
Of course, another possibility is that upon falling behind, Denver is forced to open up their playbook, and Tebow matches Cutler score for score, and it's anyone's game, as it happened in Minnesota. Or, Cutler goes back to his erratic ways, throws a couple of pick-6s, and Denver wins easily.
My point is, your obvious attempt to discredit the Denver victory is really baseless. The two teams played the game with the players they had, and Denver won. It was an inexplicable victory for sure, but definitely a total team effort. Tebow, Prater, and the defense all did their job in the last 2 minutes and OT.