I can’t understand anyone advocating six teams for the CFP. We complain about how subjective the process is now, and you want the committee to subjectively give two teams the ultimate advantage of a bye ? As someone else said, the difference between 2,3,4 is often way too subtle to give out byes.
Byes work in the NFL because it’s based on completely objective criteria. Nobody selects who’s getting a bye, they simply look at the standings and predetermined tie breakers if necessary.