Looking at the 7 undefeated teams that still are truly in contention for Top 4, sorry Baylor and others.
Clemson Alabama LSU Wisconsin OSU Oklahoma Penn State
This really becomes much more clear after Bama/LSU, OSU/Wisc and Penn St/OSU play as at least 2 of the 7 then become 1 loss teams. The one loss is bad enough for a team fighting to stay in the hunt against no loss teams, but that loss also can take that team out of their Conf. Champ game and leaves it on the outside looking in with the exception of Oklahoma. Yes a team w/a reg season loss and missing their Champ game could go in over a Conf Champion but I cannot see a scenario where they could go in over an undefeated Conf. Champ, maybe I'm wrong.
Though blasphemy, If USuck somehow got ranked before Clemson plays them, it would be quite helpful. Also an ACCCG foe being ranked will help.