Rather than just take an assertion at face value, I did a little Google work on the idea that the MAC wants to expand to 18 members. I couldn't find it anywhere. What I did find was this interview: http://www.appstatenation.com/2012/09/04/conference-realignment-mac-commissioner-talks-expansion/
Best I can make out of this is the MAC is in no hurry to fill a 14th slot and I can't imagine that they are even entertaining 18.
Could a UNI fan please post a link that indicates the MAC to 18? I'm not saying the MAC isn't moving in that direction, but I can't find any indication from my research.