I just don't think that's the case:
Given how many teams need QB's - NYJ, NYG, NO, LV, CLE, IND, TEN - and how few FA options there are out there, I think he'd likely have gone top 15-20 by the time it's all over. No one had Nix or Penix as top 15 picks in December last year either and QB's tend to move up due to the scarcity.
But yes, if it's true he wouldn't have gone until the 2nd or 3rd round, he probably makes more staying in school. But he's has to get out of State College - you can make more and develop better somewhere else.