Well they're certainly not always going to get it right. But they should learn and it's use should improve.* sometimes
I certainly like the way that play just carries on, unless the team back at base have spotted something important. Not challenges from either team, no new time wasting.
When the ref does get called to look at something, does he see what we're shown? Because the best angle to show Sweden's penalty was shown to us after the ref had already changed the decision.