This is the most incredibly stupid argument I've ever seen. QB rating can EASILY be skewed, especially if you don't throw very often (I wonder why Denver doesn't throw more?). One big play can save an otherwise pathetic day, in terms of QB rating (See: Tebow's performance against KC). That doesn't mean the guy actually had a good game.
His 5-0 road record came against teams who are a combined 22-34. In his two games against above average or better defenses (Detroit/NYJ), he sucked hard.
He completes less than 50% of his passes. That should be a BIG hint that he isn't much of a passer. Every blind squirrel can find a nut or two (big play). That handful of big plays from poor coverage skews his rating to the high side. And don't give me "they lull the defense to sleep" argument. You know who else made his living through the air by relying on his ground game to "lull the defense to sleep"? Josh Nesbitt. Tebow's better than Nesbitt, but then the defenses he's facing are better than what Nesbitt saw, too. It's the same rhythm on a higher octave.
