I think it would be advantageous for BYU to join the Big 12, even without Texas & Oklahoma, because of the stability that would come with a conference schedule as well as the post season opportunities. BYU would have the highest attendance and be one of the schools that shapes conference decisions. A reeling Big 12 would also need BYU More than BYU needs them and are likely to give BYU favorable terms when joining and maybe even a say in who they rebuild with.