Jason's two bad knees forced him to become the Heisman winning quarterback. Not saying we don't do as well with no injuries to him, or that he doesn't go on to win the stiff armed trophy, just that his injuries helped him become the football player we came to know and love.
I've seen Manning play the last 2 years a lot because he's on TV a lot he's never been a good QB. This year he actually had recievers(a healthy Shockey and Burress along with Toomer and others) and he's actually worse this year then he was last year. I think he threw 10 INTs his last 5 games or something like that. Also I'm not sure how Young's skills equate to the NFL right now. I don't know if he'll ever be better then average in the NFL as a QB. Now as a WR or TE he could be dominant IMO.
And a lot of defenses double teamed Burress...which should have made for many more completions to Toomer or Shockey.