If they were to do this system right (and the NFL has the system HORRIBLY wrong, by the way), any replay could and would be done with only an additional 30 seconds added onto the game. You need a replay official who's up in the booth, or... heck, anywhere. Watching the game on 6 TV's. If a call is wrong and it's challenged, he already knows it before the home plate up gets to the phone or whatever it is to contact him. The idiocy of the NFL of having a ref look at a tiny monitor, and spend 5 minutes going to and from the monitor to midfield is ludicrous. If you watch a game on TV, you know the outcome of the replay within 30 seconds the overwhelming majority of the time. If they had a booth-referee who only handled replays the same could be done in the NFL.