BYU has always been one of the most physical teams in the country. I think part of it is that they are a little older than most squads, and a lot of it is that they have a great coach that teaches fundamentals and gets his players to destroy the opponent without playing dirty. BYU had a heartbreaking loss last week. They had a receiver wide open about to catch the first down which would have ended the game and the ball bounced off the receivers hands into a Virginia DB's numbers.
That said, I think this is Mack Brown's last season. This Texas team is the least disciplined team I have seen this year. They roughed a punter, they had 12 guys on the field on a TD run, and the refs have been looking the other way. Texas defense looks like it is offsides on about 1/4 of the snaps. The tackling has been terrible, and the Texas D is over-pursuing. No one is maintaining assignments.