Personally, i think goal line technology should be as far as it goes.
Whether a ball has crossed the line or not is fact. It either has or hasnt. Though you would need to limit it as that, otherwise it could end up using it to determine if the ball has crossed the line on a throw-in, or a corner, etc.
Offsides is also a difficult one. In one instance, a player being in an offside position is fact. However, the offside rule has evolved, its not just enough to be in an offside position, not a decision needs to be made on if they are interfering with play, whether its 1st phase or 2nd phase of play. Even after games, you will often find difference on opinion in these instances. I think these matters of opinions should be left to the human officials interpretation.
I do however think that video technology should be available to the 4th official to spot incidents of serious foul play. (Incidents off the ball if the ref hasnt seen it). Such as the Zidane headbutt.
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