A really good SEC Champion coached by Nick Saban that most think will win the playoffs isn't the inclusion that the committee got wrong.
Where they got wrong was dismissing an unprecedented on-field cheating scandal and allowing the team that has already been (partially) disciplined for it (and tacitly admitted wrongdoing by accepting said discipline upon withdrawing their legal challenge of it).
The CFP committee considered the "special circumstance" of a QB injury in order to disqualify a team, but it refused to acknowledge the high probability that another undefeated team will vacate anything it accomplishes.
Roll tide.