IMO, the biggest possible obstacle to UNC going to the SEC or Big 10 is that the UNC System BOG and even the state legislature may well be reluctant to allow UNC to leave for greener pastures and not NC State. As much as State hates us, I'm not so sure they would be willing to let us leave if they can't join us, especially if it meant they couldn't go to the SEC as well (I don't think the Big 10 would be interested in State, to be honest). And if State couldn't play us in sports every year it would be a big blow to their finances, as I'm sure we're a major draw for their fans in nearly every sport. Little Brother may well try to prevent Big Brother from leaving them for greener pastures if they can't tag along too.