I'm not sure. I think for ball over line etc where the ball can be chipped. Objective. It did cross the line or it didn't.
But in normal play and where the decision is subjective - just look at what happens to the pundits - they sit there in their cosy office, twenty million screens, cameras from all angles, computttters that predict where the ball would have gone if it had been deflected by .0005 of a degree - and the upshot is that they still don't always agree on whether it was a penalty/foul or not. The replay can show the ball touching the hand - but can it show intent? The replay can show a foul - but was it malicious and warrants a yellow or just mistimed?
To me the answer is and always will be 'respect the ref', 'respect the decision'...hard to swallow at times - true. But it's all swings and roustabouts anyway. What decisions got Chelsea through to the final in the first place (.....oops, going down the metaphysical again....) - does anyone really complain that much when the decisions go for you? No.
So if you're willing to take the ups, then take the downs.
I liked Arshavin the other day, when it looked like he was fouled in the box - and he got straight up and pointed to the corner flag. He went up in my estimation 100%. Fair play.