Omni - Lots of things have a prayer of happening. This particular fantasy appeals to people who long for the old Big East conference.
If I'm in the Southern schools group within the ACC I have to be concerned about reaching a "tipping point" in which the ACC is no longer what it once was. Big East fans should be able to identify with that as they prepare to watch two C-USA teams battle for the Big East championship. (Chis Mullin, Ewing and The Pearl are distant memories)
If ND were to join a Conference, The Big 10 has to be the runaway favorite. Afterall, they have already been invited once and came close to accepting. The Big 10 makes sense for them geographically, historically, culturally and logistically. The only argument for the ACC I can see is that the smaller size of the ACC schools seems more compatible with ND's.
Some excellent thoughts in your post. But I think the ACC has passed the "tipping point" already out of necessity. And this is because of two major factors - football and TV markets.
The ACC was the most geographically tightly-knitted conference of them all as well as being the greatest 9-team basketball conference ever (with only the Big East capable of matching it for a short period of time in the 80s). It was never truly a football conference and only regarded slightly above the Big East in that sport mainly because the BE's dregs were worse than theirs and because Pitt was such a horrible program during the 90s.
Expansion back in 2003 is when I believe the league fought its fight against "northern aggression" in terms of college athletics and is why VT beat out SU for a spot and even had BC put on a backburner while they searched in vain for another "southern candidate" (Florida, Georgia, and Kentucky all contacted) or at least a football King (ND) if they had to settle outside the South.
When that failed and they ultimately expanded with Miami, VT, and BC they were hoping to become a real competitor to the SEC in football. Unfortunately they basically became SEC-Lite, even with VT (which has been their best football program) over SU. In the meantime, the SEC has become a monster in football that no one seems capable of catching. I suppose eventually the SEC will come back down to earth somewhat, but as we all know perception in football is even more important than reality so even if that were to occur the latter part of this decade, it wouldn't be widely begrudgingly acknowledged until toward the end of the next decade at best.
I think the ACC knows now that even though they won the initial battle against "northern aggression" back in 2003, the "southern strategy" has taken them as far as it can - which is close to being Big East level in a new collegiate landscape that is likely to place the Big East at the CUSA/Mountain West level of the previous landscape.
They will never rule the South in terms of football as long as the SEC is around. And as repugnant as it may still be to the power players in that conference, I think they are slowly realizing the only thing they can do to try and turn things around so that they don't potentially lose members to the SEC, BiG, or even the Big 12, is change up the game - give up trying to be top dog in the South and rebrand as the top dog for the entire East Coast. It's obviously distasteful to them, considering the stealth expansion with SU and Pitt with very little fanfare even after the deed was done.
As for ND, I don't disagree with anything you said. But I do believe that the moves the ACC has made in their past two expansions has taken them from virtually out of the running to almost 50/50 with the BiG.
Cheers,
Neil