Anyone who watches the NFL could have seen that the league trying to make pass interference calls reviewable was going to be integrated into the game as seamlessly as a brick in a washing machine. Somehow, it's managed to be even worse.
Given the subjective nature of the call, referees and coaches alike have little-to-no clarity on what constitutes pass interference.
So why is this even in place? Because New Orleans Saints fans continue to throw hissy fits to this day over the missed call in last year's NFC Championship game and the NFL needed a way to shut them up for a bit.
Rather than create clarity and advance the cause of "getting the call right," the league has gone totally off the rails. Such calls are rarely overturned, obvious non-calls and flags are not being challenged as a result of indecision, and there appears to be no solid answer as to how to fix them in sight.
Nickell Robey-Coleman changed the league forever, but not in the manner he was hoping. The refs are going to miss pass interference calls and then miss them again upon review because the league doesn't want replay review affecting the game at such a high magnitude.