There were MANY national media covering the conference realignment in the same manner. At that point, EVERYBODY was talking about it, and there wasn't much that Miller could say that was going to make it any worse. But what he does in regard to the personal rumors is more along the lines of "nipping it in the bud". I will grant you that it's not necessarily the most principled way to handle things (talking about it because no more damage could be done).
And the Big 12 is not very stable. That's a fact. Any conference that Texas is a part of will live under their thumb, and eventually resentment mounts (see: Nebraska/CU leaving)