My point is that even after looking at replays, decisions are still contentious. It's not like cricket where it's either an edge or not. Would you have given a penalty against Dunk last week?
With the red cards, if the ref blows up as he thinks it's a red card and it turns out it isn't, what...
I've already listed a whole host of unworkable scenarios on another thread but another one struck me yesterday. 3 minutes added time, there's a contentious penalty shout after 2 and half. 30 seconds later the ref blows up, players start walking off then 2 minutes later the video ref decides it...