IMO Bama would be left out. You'd basically have four one loss teams (AU,MSU,Baylor,and Bama) for three spots. They're all conference champs except us. In this day and age of "every game is on tv", one of the main goals will be to put as many people in front of tv's as possible. How do the ptb pacify the network that paid millions to broadcast this playoff? By providing entertaining games with nation wide appeal if at all possible, and a possible all SEC rematch ain't it.
Unless it's just "cut and dried" you'll seldom if ever get two teams in from the same conference, particularly the SEC. Now it's going to be about "entertainment value", quality of football will be further down on the list of priorities. A couple of years ago during the Bama/Okie St. debate, I read an article where over 60% of people surveyed said they wanted to see Okie St. play LSU, but over 80% thought Bama had the better team. We made it...just barely, and a lot of folks didn't like it. So now we have a "committee" with new criteria to avoid an unwanted situation.