1) Greatly reduced chance of injury.Has anyone come up with a reasonable explanation why he quit in the middle of the season yet? We can all come up with tons of reasons why he would be better waiting until the end of the season, but there isn't a very strong argument for quitting in the middle. If he gets asked that question, someone please post the answer.
2) Wants to start at a new school in spring semester. Hard to do the recruiting thing after FB season if you want to start a new school spring semester.
3) Knows his heart and attitude aren't in it anymore (discouraged and/or bitter about real or apparent backup QB status) and doesn't want his attitute to spread to teammates. (1 big drama moment instead of 1/2 season of disgruntled drama.)
4) Doesn't want to spend the rest of the season as backup--and as a result reduce his value to potential transfer schools (he can argue now that he was even with AA but didn't quite get the PT needed to show his full potential).
5) Saw how the Wesley thing turned out and thought this might be better (rip the bandaid off quickly).