The truth is the opposite. ND needs the Big12 to expand... and into good markets to remain independent.
And everytime this comes up, the most important thing to watch is Texas.
If the league doesn't do something to ensure Texas is happy, they walk to any conference they want. You are then left with 4 super-conferences and ND football is forced into the ACC. The Big12 needs to add 2 but could add 4 or 6 of the following: Temple, Houston or Rice, San Diego St. UCF, USF, Cincinnati, New Mexico, Tulane (don't laugh) and BYU. SMU doesn't help them, they are already in the market with TCU. Boise is a crap market and travel cost for such an outlier isn't worth it. Boise will end up in the PAC full time someday, they are already in it for some sports. My guess is the PAC wouldn't let the San Diego market get away either.
BYU makes perfect sense for the Big12 as it gets them into a big market, the PAC has no desire for them with Utah on board and they have no current affiliation to muddy the transaction. The Houston market is the largest in the country not in a Power 5. Temple and Philly are next. Though my guess is the ACC would snag Temple if the grabbing starts.
I think it's inevitable that college football / basketball end up in four, 20 team conferences. Money, the aspirations of school presidents and the nature of change as progress guarantee it.
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