was promoted after coaching one of the worst defenses FBS had ever seen.


I don't know that you'll find a "perfect example" to illustrate a guy getting promoted after being part of something awful. Dabo Swinney comes semi-close, getting promoted from WR coach all the way to HC after being part of a staff that got the HC fired for underperforming on both offense and defense, but then he sort of proved himself during his stint as interim HC.

Nobody on the current defensive staff for BYU has had a chance to prove themselves.