I was going to post an old article last week about why Big almost 12 wouldn't expand, but felt it was beating a dead horse. But, for you, here's what it said (the author's opinion- it was in an Utah BYU newspaper). Conferences have Tier 1, 2 and 3 games. The 1s and 2s go to the big boy networks, and the 3s are the one's the conference can sell to other places. That is where conferences get their extra money in addition to their ESPN or whoever contract. That is the only reason the Big 10 wanted Rutgers, because now they could force the cable channels in the New York area to carry the Big 10 network. They get $1 per month per subscriber, and when New York opened- they gained big $$. The network pulled in an extra $7+ million per team last year (whatever year that article was talking about). The Big 12, because of Texas, can't sell their Tier 3 games for much at all, because there is no Big 12 network. So, if they add teams, each team loses millions because they have to share the same 1 contract. No reason to expand.
So, if anyone knows differenth than this article, please correct. But, unless they can find away to create a market for the Tier 3 games, unless they can re-work their TV contract, unless the universities decide to not be that greedy, then it looks like they're more than willing to be least of the P5, no matter how many times W. Virgina leaks about expansion.