I'm sure this has been discussed before, but I haven't been following the board that closely. My major concern is this persistent 3-man defensive line, with the linebackers playing way off the line. I don't think I've ever seen a BYU defense use this style so repeatedly. It seems like a recipe for failure against most teams. The opposing QB has all day to look things over. Just like Beck to Harline, dropping a lot of people in coverage won't get it done when the QB has that much time.
I believe we beat Boise State because the defense became more aggressive, and we often rushed the passer with more than 3 guys. However, for some reason we went back to the "prevent" style after Boise State. I think this was the biggest reason that the Liberty game was close. I fear that Tuiaki will continue with this 3-man rush fetish, and will become more of a believer in it when we beat Idaho State and UMass.
I doubt we'll beat San Diego State or win the bowl game unless we return to the aggressive D we saw against Boise. This "prevent" defense is a bigger issue than who starts at QB.
My minor concern is kickoff returns. Why is Katoa doing it? He's not fast enough to break a big one, and it's an injury risk to have him do it. We're not exactly deep at running back. Either put a speedy guy who is a real threat back there, or put someone else in who will just field it, and save Katoa for RB duty.