I have no horse in this race, but after listening to whining from many (not all) USC fans after Jim Harbaugh went for two on his way to putting up double nickels against Petey, it's clear that Trojan fans and their coach have not learned any lessons about sportsmanship.
Carroll's logic in sticking it to UCLA Saturday night loses all credibility when you watch his reaction after the touchdown. As one person put it, he was "celebrating like a 13 year old at a Miley Cyrus concert." The Trojan players followed the lead of their coach, inciting the Bruins and nearly leading to an all-out brawl between the teams, the likes college football hasn't seen since Florida International and Miami played in 2006.
There's no degree of separation between the decisions by Harbaugh and Carroll. Simply, each was a bush league move.
Updated: Video after the jump shows Barkley taking the knee, Carroll discussing options with offensive coordinator Jeremy Bates, and the touchdown pass.