He was convinced to come back, but I think Hill's bombastic ways were documented before, if you remember what Jordan Pendleton said about him. I can't remember exactly what JP said, but I believe Jay Drew wrote something about it:
http://www.sltrib.com/byucougars/ci_10196892
This former cornerback also said that doing the FSU game, the whole defense felt like Jaime was holding them back not only that game, but the entire season (clearly they had more issues than that--tackling 101, for instance). He never let them play up on the receivers, and he was very timid in his blitz calling. He said that Hill didn't trust them and constantly screamed at them from the sideline. This was mentioned above, but only a certain type of personality plays up for this type of coaching. Finally, according to this player, Bronco asked Hill if he could give him a suggestion during the FSU game, and Hill reportedly said something along the lines of: "You hired me to coach the defense and that's what I'm doing", if memory serves me correctly.
I remember going to the airport to meet the team when they beat Oklahoma. All the coaches, even Anae, walked through the lines and gave high fives to the fans, and Coach Hill walked as far away from everyone as possible. This may be a microcosm of his tenure here in Provo, or it might not, but I couldn't help but notice that it seemed a little odd at the time.