The purpose of the College Football Playoff selection committee is to sort through the unsortable -- deciding between two teams of similar accomplishment.
This sport is a spectacular mess, of course, famously and belovedly so. The FBS level has 136 teams playing 12 regular-season games competing for one championship. The schedules are disparate, even within the current oversize "conferences."
No one would design such a thing. Big schools. Small schools. State schools. Religious institutions. Even three military academies. From L.A. (Los Angeles) to L.A. (Lower Alabama). It's glorious.
If a proper computer formula exists to figure out who should or shouldn't be in a playoff, none has earned the trust of the sport.