The CU add may have been done early to push back on Baylor manuevering. The original target list was UT, Tamu, TT, OU, OSU, CU. Baylor was trying to push for a Texas quad, which would have bumped CU out. But PAC had been eyeballing CU and UT for decades. So, PAC added CU to shut the door on add-ons and force the realignment issue. That was the trigger for the B10 to grab Nebraska, which put the B12 on an accelerated path to make decisions. Texas A&M was reluctant to follow UT into the PAC, triggering their conversations with the SEC. In the end, no one else jumped from B12, they added TCU and WVU instead. And the PAC added UU to get to a sensible 12. Then the A&M and SEC pulled the trigger, drafting UM in their wake to get to an SEC-14, and setting up the current B12 drama.