If everybody's trying to poach the ACC and schools are listening, why wouldn't the state of Virginia want to see its schools land in the highest revenue conferences -- one in the SEC and one in the B1G?
Politically, it might be difficult for one to leave the ACC and abandon the other in a diminished conference; but if both find a good home at the same time, then it's hard to turn down an extra $25 mn/year coming into the state.
Suppose it's UVa to the B1G and VaTech to the SEC. Then the decision-making moves to North Carolina and UNC, Duke, and NC State.
UNC and NC State also have a shared governing board and they will also demand that both schools find good homes. So though the SEC would much prefer UNC, if it only wants one state school in the state and B1G doesn't want NC State, UNC will be compelled by NC politicos to go B1G so that NC State can have an SEC home.
So B1G gets UNC and UVa for 16. But Duke is up for grabs. If they take Duke and UConn together they'd have a fantastic basketball conference and would cement the eastern seaboard. Duke is happy to be playing in NYC, they've always wanted east coast exposure. UNC is happy to have Duke in its new conference.
With the ACC broken and losing its top east coast schools, Notre Dame is independent again. They could align with the Catholic 7 for other sports. But now that the B1G has an East Coast presence, it's much more attractive to them. Let's say ND joins at some point. No telling who the partner might be (could Kansas be pulled from the B1G?) but let's say ND asks the B1G to rescue the other BCS Catholic football program, BC, bringing the B1G to 20 and giving teams a chance to play in Boston.
Other top ACC schools FSU, Clemson, Ga Tech, and whoever else the B12 finds attractive land there.
Fox has improved its position vis-a-vis ESPN tremendously. The SEC covers all of the South. the B12 picks up 6 teams for 7 eastern teams in a 16 team league. There's a new ACC/BE leftovers league formed of the best of the rest.
Too many variables to predict, but this seems like a plausible scenario. B1G, SEC, B12 negotiating amongst themselves and with Fox and ESPN about how to break up the ACC. University governing boards and state politicians figuring out their desires. Back contacts back and forth. They will find the best mix. I think the state of Virginia holds the best hand and can force one to the SEC, one to the B1G. Once North Carolina gives up on preserving the ACC, they follow a similar strategy. That leads other teams to jump for the B12. Dominoes may fall quickly.