TV evidence should definitely be used for goal-line incidents, to determine if the ball has crossed the line or not. It's amazing how often they get this wrong.
Other than that, I don't think there's a need for it for any other scenarios, as they tend to even out over the course of a game.
It's equivalent to what happens in rugby union, when they go to the TV screens when it's not obvious if a try has been scored, or in cricket, when they go to the 4th official to see if a batsman was run out.
Waiting for the TV decision in these situations actually adds to the excitement, and they are usually so infrequent that the game isn't disrupted too badly.
Bookmarks