plus the exhilarating thrill and sudden joy of a goal will be sucked away as we wait for 5mins for a guy to sit in a booth analysing every last detail of the lead up to see if they can find anything wrong with it.
See: NRL.
Imagine the nix scoring an injury time winner in the Grand final next year, only to have the joy sucked away as the referee goes upstairs and we wait 5 minutes to see if Kostas big nose strayed a millimetre offside. What a downer.
The obvious rebuttal to that is "what if the nix concede in injury time to lose a grand final and the goal was offside" - I figure there is a margin of acceptability that sucks to be on the wrong end of, but you can understand why the ref gave it. Even then, while it sucks when those wrong decisions go against you, such incidents add to the drama and even become a part of club legend - like the hand of Payne goal against the nix.
Now we want to lose all that and make football a series of robotic decisions? No thanks.
And how far back do you go? What happens if Kosta was a nose off side, and we score a goal after keeping possession 30 seconds later? 90 seconds? 5 minutes?
that's a massive problem in the NRL system that adds an entire layer of inconsistency that wasn't there before.
Referees very rarely call things like obstruction live now, preferring to let things go and check it if a try happens to be scored. This means if there is a hint of obstruction a team is better off taking a tackle on the 1m line, playing the ball, then falling over to score, when it won't be checked (they only check last tackle).
To translate that to football: linesmen may stop calling borderline offside calls. The cost and criticism of calling something borderline (or when you are say 90% sure) and getting it wrong is greater than letting it go then checking it later. Once you make the call live you can't take it back. So linesmen stop putting their flag up for borderline offsides. Very few of these actually result in goals, but a lot probably result in corners. What if a team scores from the resulting corner? That seems to add a whole new layer of inconsistency to the game, that will actually happen more frequently than it does for a goal.
This behaviour of deferring to the video referee is completely understandable. If you make a call and it happens to be even fractionally wrong people will criticise and say you should have used video replay. You even see it in cricket when a player gets run out and is literally metres out of his crease - the umpire is 99% sure he is out, but that 1% of doubt ridiculously causes him to go to the third umpire almost every time.
So video referees can actually lead to more incorrect decisions, than it managed to fix incorrect ones because it alters the general decision making behaviour of referees.