You should be a conference champion before you play for the national championship.
How about you should play in a conference championship game before you are a conference champion.
No, I don't think this is right. I go along with the setup of each conference's championships, whether they have an extra game or not. OU are not conf. champs, LSU and USC are, each by their own conference rules. It shouldn't matter that USC did not play a conf. championship game, they are still number 1 in the nation.