I have guided duck and goose hunters for many years and most have no idea if they have actually hit the bird that drops but say they do. Almost all have pumps and semi's and fire all 3 shots at every flight. 3 birds come in 5 hunters unload and one will actually swear 'he' shot them all. I budget 3 boxes of shells for a limit of 8 birds per hunter. That's 10% success 'if' a limit is actually taken.

On the other hand, watching them makes me a much more patient shooter and my success rate is closer to 35 - 40%. But I do use an over and under and often wonder if my success would improve with a single shot.

Nothing is foolproof to a sufficiently talented fool.