Why Pitt?
Texas needs ND and they need leverage to get ND to make the move. As we all know ND plays their other sports in the Big East. Their football team can stay independent for awhile but their other sports must be in a conference. So, Texas' best option is to help facilitate the break up of the Big East, or at least make it seem unstable enough that ND wants to jump that sinking ship. The ACC has also been rumored to be looking at some Big East teams, especially if SEC #14 (15?,16?) come from the ACC. So why Pitt? Its not about wanting Pitt, its about what Pitt jumping ship does to the Big East and creating inertia for ND to do something.
How about this?
Aggie leaves and the Big 12 adds Pitt, WVU, L'ville, Syracuse, Boston College and Navy. That puts us at 15 and pretty much destroys the Big East. Notre Dame's home for the non-football programs is in trouble. The Big 12 offers the final spot in their new "Big 16" to Notre Dame.
Notre Dame plays Pitt, BC and Navy pretty much every year and has some history with Cuse, so there would be some history that would make this attractive to them. Plus they have a strong presence in the northeast from a fanbase perspective and this allows them to play a lot of northeastern schools.
The eastern half of the Big 16 would be:
Notre Dame
Pittsburgh
West Virginia
Louisville
Syracuse
Boston College
Navy
Missouri
The western half would be:
Texas
Texas Tech
Baylor
Oklahoma
Oklahoma St
Kansas
Kansas St
Iowa St
If we happen to lose Mizzou to the SEC in the process, add UConn or Cincy or Rutgers to fill out the eastern half of the league. Notre Dame would be in a conference where they would play 7 games against the eastern half of the Big 16, which includes at least 3 of their regular rivals. They could also play one or two crossover games with the western division (annual matchup with Texas on Thanksgiving?). The two halves would essentially function as individual conferences with some strong scheduling ties (which is what super-conferences are anyway...).
TV networks would love it because the conference would have a strong presence in the highly populated Northeast as well as a strong presence in the highly populated state of Texas. It would include some powerful tradition-rich programs. The annual championship game could alternate between Cowboy Stadium and the Meadowlands, with a stop in there every once in a while in Indianapolis. The basketball tournament could be on a rotation from KC to Dallas to NYC.