All I'm hearing is "well obviously these other teams aren't as good as Texas or Florida/Alabama." And that's exactly the point that Theogt and other are trying to say.
With 5 undefeated teams, we're just going to end up saying Team X and Team Y are better, so they will play for all the marbles. Then you have a bunch of teams that all they did was win all the games they had yet have no opportunity to prove themselves as the best. That's the best argument for a playoff system that there is.
Also, to the point of "schedule better opponents"... that type of argument works for the Utah's of the world, but doesn't work for Iowa, the Big East teams, or for Boise, who have actually tried to schedule tougher opponents, even on the road, but have found it hard to convince people.