has 12 teams that likely aren't going anywhere; so even if UO/UW have "wandering eyes" the conference itself is still stable.
I'm NOT convinced that Big Ten and SEC go beyond 16 teams, so if Big 12 gets Colorado, Oregon, and Washington (plus one more to get to 16), it cements itself as the #3 conference in football and the #1 in basketball.
Oregon and Washington can only leave if the Big Ten offers them a lifeline. Better to have them in our conference than not; regardless of whether that lifeline ever comes. Any expansion with Pac 12 teams is done for one reason: kill the Pac off and become #3...I'd rather do it with 2-3 teams from the top than 2-3 teams from the bottom.