Time and time again I see situations in football matches that would have greatly benefited one of the teams had the correct decision been made - and had the referee used the screen which would have been of no hindrance, the correct decision would have been made.

For example:

In the Chelsea vs Man City game on Sunday, I think it was Aguero made a straight-red-worthy tackle on either Mata or Suarez (I can't remember which). The referee gave a free kick but no card as he hadn't seen the second, far more rash, part of the challenge. The rash part was clearly shown on the huge screen, which the referee saw. However, he wasn't allowed to issue the red card after seeing it - an absolutely ridiculous thing.

In the World Cup 2010, Argentina scored a knock-out goal against Mexico, which was actually offside. The referee couldn't make the final decision based on the on-screen replay.

Lampard scored a goal which bounced back out, but the referee didn't allow it, even after seeing the replay, because he wasn't allowed.

In Rugby this technology is made great use of, and it makes for a far better and fairer game, with tries only being awarded if they were actually tries.

Why can't referees look at the video and make the decision? It would really make hardly any difference to the length of the game - perhaps it would add on an extra several minutes (3 minutes is really no problem). It just seems absolutely ridiculous, and no one I've spoken to is in favour of the rule.

So why is it that whoever runs the football association doesn't change this?