Two main reasons in favor of the CFP was to make sure there were no rematches, and that teams that hadn't won their conference wouldn't have a chance at a NC. Here we are, just a few years in, and we are on track for at least one of those. Maybe both, depending on how crazy the committee gets.
#2 OSU beats #3 Michigan, but neither are going to be conference champions. It's hard to justify lowering OSU's rank to #5 for beating the #3 team when you didn't lower the rank of the #3 team for losing to an unranked team. On the other hand, the committee may only lower Michigan one spot for losing to OSU. Which would cause a rematch. If Penn State wins the B1G, how do you leave them out but include OSU? If you drop Michigan out of the playoffs, and put Washington in, how do you justify that to Penn State if they win their conference and beat OSU?
When everyone was calling for a playoff system in 2011, I told you that it would only ensure rematches and teams that hadn't won their conference getting into the playoffs. It didn't take long.