Agreed that it should be claimed. The primary argument against it seems to be that we would not have been undefeated if we played in a bigger conference.
So what?
Look back at the NC teams before the BCS or playoffs. The schools that got those championships did not go through a playoff system or necessarily play the hardest schedules. Do those schools revoke their championships because they would not have survived in a better conference?
It was always just a beauty contest. And there are some polls (i.e., beauty contest judges) that named Utah the national champion.
Saying Utah would not have done well enough in a major conference is irrelevant. They won every game. That is undisputable. Saying they would have lost with a different schedule is both speculation and irrelevant. You could speculate about that with any team (i.e., if X team had played Y team that year, they never would have won the NC).
I say claim it. No need to be obnoxious about it. But barring a playoff, it is just a beauty contest, and there were some judges of that contest that said we were the best. No reason why those polls should have any less credibility than others.
Utah @ 
Arizona State .
