I find it is much easier to kill a goose or duck with a head/neck centering shot. For Canada Geese, I want to hit that white patch on their head every time. You can usually tell those kills when the head and neck drop and the bird folds up immediately. Much easier than trying to penetrate the body with heavy feathers and a butt shot means you'll be running after them.
My main advice would be that you gun must always be in front of the bird to kill it, regardless if it is 15 yds or 50. Keep your gun moving, as it ensures that your shot is indeed in front of the bird, and if you miss, you are usually afforded an easy second shot. I have several POV videos that you may want to watch, as they show the different types of leads (sustained, slow and fast english/pull through, snap shooting, and sometimes more than one method on the same flock. Here is an example:
That’s the trick. I start thinking, shooting goes to sh!t.Personally I don't think about it. Just like throwing a football to a person running. I would be curious how many do the same?