There are plenty of permutations and hypothetical scenarios. But maybe the most basic one for the BIG12 and CFP is pretty simple.
The BIG12 hopes (bets) that there will be an upset in a Conference Championship Game. As we saw, when strong teams win CCG's, they get into the CFP over strong teams that did not play CCGs. I think that is the very clear message of 2014/2015, and has been confirmed by the committee subsequently.
Everybody knows that there will be upsets in CCGs. But the fact that upsets occur doesn't make betting on the underdog EVERY TIME a smart strategy. In fact, that is horrible strategy.
It isn't a perfect analogy, but that is what the BIG12 is doing in some regards. They are betting, every year, that the winner of a CCG will have a worse profile than the non-CCG playing BigXII. That happens, but it isn't a smart bet.
- What would really blow the thing up would be if a team lost a CCG and still got in over a BIG12 team. Is that really that far-fetched? A 3-loss CCG winner getting in over a 3-loss BIG12 "champion." Heck, that seems pretty plausible. Stupid BIGXII.