The sideline tussling occurred because the stadium jumbotron showed the replay immediately and everyone, including the referees, knew it was a blown call.
The on field refs were screwed at that point because they would have caught hell from FIFA if they changed the call.
All FIFA is doing at this point is feuling the assumption that with video replay it would be harder to 'fix' the games.
All they need is to add a fourth referee either in a TV booth or in the TV monitoring truck, plus special camera positions to track the inside of the goal itself, to make sure goals actually count. And since video nowadays are recorded onto hard drives and not onto videotape, they could cue up and complete the review in 35-40 seconds and add that time to injury time at the end of each half of the game.
The problem with replay is that it makes referees even worse, since they figure if they botch the call, video will catch it anyway.
I would allow replay on one condition. There are alternate referees at the game. If video overturns a call from the ref on the field, the ref is tossed from the game and the tournament and the alternate ref comes in.