Good point D&DFan,
Baylor, a larger private (Southern Baptist) in Texas got a Big 12 selection when the former Big 8 took four, south, from the old SWC. Then, Governor Anne Richards, a Baylor alumnus, had a bit of influential input into the decision as I understand. Now, some are questioning the decision, noting Baylor's long-term, losing football record and the basketball turmoil from last summer.
I thought TCU's membership in the revamped C-USA made the conference look pretty good, geographically, for the future. SMU, Rice, Houston (old SWC and Texas foes), plus Tulsa and Tulane seemed like natural opponents. Though they may still continue to play neighbor town rival, SMU, the luster of the rivalry will be less.
SMU was a real force, going as high as #2, before their excessive violations did them in (going back to the 80s?).
TCU was once a long-term dormat, and Texas and A&M, ran up huge scores on them often. Good for TCU that circumstances have changed. However, when, not if, they hit the skids again, one wonders if they will regret their MWC move. As long as they keep winning, they will say it was the right decsion.
If the Big 12 had a vacancy, I would think they would not seek TCU, but rather someone such as Colorado State or Air Force, or try to appeal to Arkansas from the SEC. Of course, that is solely speculation.