It's thoroughly bizarre. There are tons of decisions at football that I question and then subsequent tv replays show me why a ref did or did not make a decision. I kind of trust that the linesman or ref is going to be better at spotting things than me sat in the stands as firstly they are closer to the action and secondly it is what they do for a living. If a ref is wrong following replays then generally the reaction is well they will learn from it in the future its unfortunate they got it wrong.
According to derry as long as he is satisfied when he sees it in real time, then that is the barometer for whether a ref or linesman should be criticised or not. Strange.