I mean... Lavell was the consummate coach/representative/face of BYU and the church.
Look at Broncos demeanor when he was the passionate DC. Then look at his demeanor after he was interviewed by the BoT and he became HC.
His demeanor changed. Stoic (mostly). He was passionate, but now very contained. He was Lavell'd.
Sitake... Was Lavell'd... Even more easily, because he loves the players etc. Be the face of BYU. Keep a clean program. Lead/develop good men etc
I would not be surprised if the BoT don't have some influence here on all of this, because they want a certain image from their HC to reflect well on the Church instead of turning them loose as to who they really are.
Not sure how that translates into W's and L's.... But I think BYU's head coaches get put into a box from the start a little bit.