I've seen more than once the idea of making PI calls reviewable being talked about. I really don't like that idea but maybe it is time to allow a review of a game changing PI call. Maybe in best interest of all. The reason there are 3 challenges is so things like a bad PI call in the end zone doesn't give a team an underserved advantage. No one wants the refs to decide a game ... it should be the players. Perhaps PI calls within red zone and end zone should be reviewable.