I read this article on ESPN Insiders on fatal flaws for championship contenders. I found it interesting that they named Braxton as our flaw. Yes I copied and pasted a small part of the Insider article.
Ohio State Buckeyes
Fatal flaw: Fourth-quarter/overtime performance of Braxton Miller
Miller led all Big Ten quarterbacks with a Raw Total QBR mark of 75.3 last season, but his performance in that category has shown a dramatic decline over the course of his career in the fourth quarter and overtime of games.
Last season, Miller ranked ninth among Big Ten quarterbacks in fourth-quarter/overtime Raw Total QBR (43.1) and 10th if the study is limited to contests against teams from BCS-caliber conferences (35.5).
This is not a short-term trend, as Miller has had 16 career starts in which the game ended with the teams within one score of each other. In six of those games, Miller posted a fourth-quarter/overtime Raw Total QBR of 78 or higher, and Ohio State went 5-1 in those contests. In the other 10 games, he posted a Total QBR of under 46; the Buckeyes' record in those matchups was a dismal 4-6.
What makes those figures even worse is that they look to be tied to competition level. The combined win-loss record of the opponents in the six aforementioned games where Miller had a Total QBR of 78 or higher was 38-39. The win-loss record of the teams in the games where he played poorly was 90-42.
This means Miller tends to play well in close games against mediocre opponents but falters in crunch time against strong opposition. If Ohio State is to make the playoff (and win once it gets there), Miller must improve significantly in this area.