I know that conference realignment is one of the favorite topics on this board, and the media loves to drive the speculation. However, there is not one post in this thread that even attempts to give one reason why the B!G or the SEC would want to expand. Start with 16 being a near perfect number for a conference in terms of scheduling, tournaments, distribution, etc. Then try to come up with a scenario where the per school payouts are INCREASED by whatever change you suggest. I don't think you can do it without the B!G and SEC raiding each other.
The fact is that neither of these conferences need more content; nor do their media partners. 16 teams provide more than enough content as it is.
Now, when it comes to the B12, PAC12 and ACC things are different. They can possibly improve their media position by adding members to generate more content. One problem they have is that most media purchasers of content don't really need any more, either. How many football games can Fox, NBC, CBS, ABC and ESPN show that they are not showing already? The answer is that the content seekers are Amazon, You Tube, and MAYBE one or two more. The amount of content these providers can show is limited. If you think these are the outlets that will generate the extra money to pay the schools, then why is it not working for the PAC12?
Why will any media organization pay the B12 more for Arizona and Arizona State than they will pay the PAC12? Same for Colorado and UTAH. Sure, there might be a geographic fit, but where is the money? The B12 has already diluted their level of play and their academics (if the ever had any without Texas), why would PAC12 schools want to get into that shallow pool?
The ACC is just a disaster that can't continue for too much longer. They jumped at the crap ESPN sold them and now they are paying the price. And the west coast connection is someone's pipe dream. If UCLA playing in the midwest is a problem, how about Miami in Seattle, or Syracuse in Tucson? And, again, you have the content problem. ESPN does not need more content. Why will they pay the ACC enough to increase their current members to SEC levels and pay the new west coast schools, too? The ONLY way out for the ACC is to end the GOR agreement, and to do that, the big schools will have to offer some benefits to the other schools to get their vote. And, if the result of ending the GOR is that the major draws in that conference are going to leave, why in hell would the other schools support that? Maybe ESPN will be nice and give them another billion dollars in the name of EQUITY. They seem to like that approach to other things.
Finally, I think if the B1G were going to expand any time soon, they would have done it when they took the LA schools. I am sure they looked at the money, the scheduling, etc. and said no.
But, hey, all this speculation is fun, right?