The simple answer as regards a penalty which could be seen very quickly (a) is it a foul or handball (b) was it inside of the box.
As regards a goal was there any infringement this may take a few seconds longer but the game will have been stopped it is just a matter of how it is restarted if...
I wouldnt argue about their incompetence but if a man sat in the car park watching a tv screen said it was a penalty then that is the answer if he says not, again that is the answer. I think that it is more likely that he would be correct with his decison.
You are trying to think of hypothetical situations that in reality probably wouldnt happen, and if they did it would be once in about two seasons or so. Rules can be placed in case of such an eventuality and probably never ever used.
It is not only offside that a try is refused for. I have seen them disallowed for an earlier forward pass, playing stepping out of play, high tackle amongst others. I do not see why the rules cannot be applied in football. In your example there would be a break in play when the other...
I would think the Video ref would have seen it and drawn the refs attention to stop play before the other side reached the other end unless of course it was a shot from the keeper out of his hands a la Paul Robinson or Pat Jennings and scored. I am not really into rugby but seem to have seen...
I must admit I do not watch rugby and am relating to when it first came in, but I wouldnt think that there is any reason for the video ref to watch an incident more than twice and make a decision. It may not be 100% correct but stands more chance than an incident like last night.
Did I read that Rugby Video Refs are sat in a TV van outside and just relay their decision to the ref. We have the tv car park ready now just need a heated camper van for the retired ref to watch the game.