I've watched Bama maybe a dozen times this season, and this assessment is pretty on. They win by outscoring opponents. And they have a very up tempo style of play and when they are on offensively they are really really good. They take advantage of defensive lapses by their opponents.
If BYU can be on par with their usual offensive output and defensively not let Alabama turn the game into a runaway freight train, then BYU has a good shot. The don't have to hold Bama in the 60s, just make them extend possessions and not give up good looks from 3 or easy buckets at he hoop due to breakdowns defensively inside.