It seems hard to believe that just 13 years ago, major college football decided its champion by means of a two -team playoff, if the Bowl Championship Series can be called that. Now, a playoff system 12 times bigger than the BCS of yore seems to be on the horizon. The ACC is united behind the expansion of the CFP to 24 teams, it indicated Wednesday—first via a press conference given by commissioner Jim Phillips , and then via a report from Ross Dellenger of Yahoo! Sports . The move puts the conference in lockstep with the Big Ten, the loudest backer of an expanded format. Phillips’s league’s shift was interesting enough on its own, but he cited as a prominent opponent of a 24-team field an entity that may surprise some fans: ESPN. “(ESPN) has been pretty clear with all of us that they’d like it to stay at 12, maybe 14, but no higher than 16,” Phillips said Wednesday via the AP’s Mark Long . What reason could ESPN have for opposing expansion? It’s pretty simple.…