In all its 2001 internet greatness:
The whole point is that it is not for just a game or two. It is usually for a couple of rounds of the playoffs or even the whole next season. You are right that it is rarely longer than that as the reasons why it works for a time most likely have to do with lower egos, underdog mentality, high level teamwork and trust. Success has a way of “curing” a lot of those conditions.
I am not saying this will happen, just interesting seeing how many boxes BYU checks.