The DoubleExtraPoint blog has an interesting analysis that attempts to mathematically justify the fake punt in the Cotton Bowl with Game Theory. It's an interesting, if not mentally exhausting read, and definitely makes some good points. In my opinion, it's flawed because it doesn't account for momentum or the context of the situation. In a 7-7 game against Ohio State or the 1995 Huskers, running a fake punt makes more sense since you only have so many opportunities and you have very little to lose. At the other extreme, in a 7-7 game against, oh, say 1-AA Maine, it makes no sense because you risk falling behind an underdog and giving them momentum.
Against Auburn, a team you are otherwise dominating at that point? I still go with: dumb, dumb call. But it is an interesting read.