This is the problem with current realignment. The Pac 12 has difficulty getting to 16 without the B12 falling apart and the 4 Super Conferences with the SEC, B12, B1G, and Pac 12 would leave the East coast with no conference. The only logical thing that makes sense is the Pac 12 sniping off Big12 teams like Texas which doesn't seem plausible at this juncture.
And I just can't see the East Coast being without a conference although I guess that is less of an issue than having the Pac 12 take on Duke/UNC.