Thank you all for your replies. The experience that prompted the question was one from my early teens. The first duck i ever shot. I don't come from a duck hunting family and never had access to decoys or a dog. My best bet was jump shooting off the small creeks outside town. It was basically a spot and stalk situation where I spot the ducks from the ridge and sneak down into the creek bottom.
I learned quickly that ducks are not stupid and are very difficult to sneak up on within shotgun range. After MANY unsuccessful attempts, I finally got within range of a big Drake mallard. I remember a couple of seconds of watching him on the water 20 yards away with a clear shot. I didn't shoot because I was always taught that shooting one on the water is a cardinal sin. I let him fly and my first shot knocked him down to the water, but he still had life left. He crawled into a thick mat of cattails. I searched for hours and never found him. For me, losing that bird was much less palatable than breaking some ethical taboo.
I think jump-shooting is a different game than shooting over decoys with longer shots and less reaction time.
