@barbarian I think thats sort of my point - if its not clear & obvious / egregious then what real impact has it had on the try being scored. If the captain didnt see the infringement, in all likelihood one of his team mates would have. If none of them saw it, and the ref didnt see it, then fair play call it a try.
I think i hold the opposite point of view to you - rugby is so technical and there are so many thin margins and grey areas in calls, that analysing every try to death through slow motion and replays just removes some of the subjective & flowing nature of the game