G5/nonBCS/nonmajor: .767 win pct. Good, but should be higher. Losing to UCF, NV, USU doesn't help and totally unavoidable.
Lower P5/BCS/major (.400 win pct. or lower): .677 win pct. This should be higher as well. I would expect this to go up when BYU is in a P5 conference.
Middle P5/BCS/major (.401-.600 win pct.): .575 win pct. Not bad at all, some mishaps could be higher, very much so. Little things like playing out of position, coaching technique will greatly change this.
Upper P5/BCS/major (.601 and above): .223 win pct. Because BYU plays fewer of these teams, this will be the most difficult hurdle to overcome. Get in a P5 conference then over time and recruits, this could easily be 55/45 in BYU favor.

Bottom line, BYU should improve on beating the beatable teams. Mid teams, BYU should stop shooting themselves in the foot and beat those teams. Top tier teams, this will be the most difficult to over come. BYU in the B12, has a much better shot at a conference championship over the long run as I believe BYU could compete very well in that conference.

Teach correctly, act correctly and stop TO. Fundamentals and no turn overs....