Not sure how he has so many Freshman, unless he redshirted the entire recruiting class last year but this looks like it could be a really good team in a few years. I'm guessing Washington will give Petersen time to develop those players.
Additionally, I wouldn't read too much into his body language last night. He was at Boise for years, coached many of the players that started for Boise last night and still has strong ties to the Boise community. Last night had to be tough emotionally, between his return to Boise and coaching against "his team".