B12 needs a network and can't do it on its own; Pac12's network hasn't been super profitable, because of its isolation from 3/4 of the country. I suggested B12-ACC join to form a 2-conference network, but maybe B12-Pac is the way to do that. It gets the Pac network three time zone coverage, which gives it a chance at an East Coast audience.
Moreover, if B12 added UConn and Cincy, and there was some sort of scheduling alliance with Pac12, then they would have effectively nationwide exposure and significant penetration in the northeast.