There isn't a measure, outside of completion percentage perhaps, where he wasn't great as a college QB. You can make an argument that he was great bc of his supporting cast, and the counter argument of his supporting cast being great bc of him exists as well.
Won-loss record: 38-2. Great.
Big East record for TD passes, passing yds, pass completions, pass attempts: great.
UM record for TD passes, passing yds, and total offense-great
86 TDs against only 28 INTs, 3:1 ratio: great.
Big East offensive POWeek 7x: great.
Completion percentage on 3rd down of games: 61.7%, 2531 yds, 25 TDs/ 4 INTs (6:1 ratio): great.
Completion percentage of 57.6% in 4thQ, 11 TDs/ 1 Int (11:1 ratio): great.
1 NC
Played in another.
2-time Heisman finalist.
Maxwell Award Winner.
Rose Bowl Co-MVP.
His career completion percentage of 57.9% is his only average stat.
There's no other measure where you can say he wasn't great. If so, prove it.