The Big XII is an irrelevant conference in CFB, it is now essentially a beefed up Mountain West and clearly a step behind the SEC, Big Ten, the ACC (with the addition of ND), and Pac 12. Like the Mountain West, WAC, MAC, and C-USA a team from the Big XII will need to be undefeated and get very very lucky to get into the playoff. Could happen once every couple decades maybe (not that it will because the soon enough major CFB will be closed off to teams outside the Big 4 conference).
OU and Texas are smart to look to land in a conference that matters (even at the cost of having less "power").
The only thing that really matters is football and the Big 12 is absolutely better than the ACC in football, as well as the Big 10. The problem with these bigger conferences is that they have so many pud schools. Take the Big 10 for example, the 14 teams in the conference include (think about football) illinios, iowa, indiana, maryland, minnesota, northwestern, purdue, and rutgers. These 8 teams are in no way better than a texas tech or oklahoma state for instance.
Michigan and penn state are big names, but recently they simply haven't been competing at a high level.
Then you have Nebraska, Michigan State, Ohio State, and Wisconsin. Admittedly good teams, but not really more so than Baylor, TCU, Oklahoma, and maybe K-State the past few years.
They may have 1 more good team, but over half of the conference is complete garbage.