five "autonomous" conferences. That means that even a gutted Big12 has more power than the AAC. Also, the Big12 currently has the ability to cherry pick who it wants to invite from the G5 to add to the conference's roster of teams. Seriously, who "wants" to join the AAC with its current membership?
Far better to raid than to be raided. Even without Kansas, Iowa State, and WVU (ACC/B1G targets) the remaining five teams can still hold the Big12 together if they act quickly to fill the holes. Invite Boise, BYU, SDSU, Houston, Memphis, and UCF immediately. Then, if the Big12 loses more than OU/UT, they already have a plan in place.
This really isn't that difficult. And, given the impending CFP changes, BYU would be dumb not to join.