As Len and Bob have pointed out, games are delayed by arguments over calls all the time. With an extended replay system, you circumvent the argument and go straight to replay. In the final equation, it probably won't make any difference with regard to "ruining moments". There's no need for it to be instant. Moving past a bad/disputed call is never instantaneous. When has the delay ever resulted in an overturned call, though? I vaguely remember one time, maybe, from when I was a kid. The opposing manager can argue till he's passed out, but once the umpire calls safe on the game-winning run in the Cubs' pennant clinching NLCS win, I can be fairly confident that it's decided. Well, maybe not "ruined for me," but I'd enjoy it more without it.