Wow this is timely... I was just talking about this with my shooting buddy, and we were recalling a shooting session early last fall.
We had been shooting a lot of 22 at various ranges. And yes, when I shoot a 22 from a standing position, I look a lot like the stances pictured above... highly bladed, left arm directly under the rifle, left palm close in, under the center of gravity.
So at the end of the session, my buddy suggest we pattern our shotguns to prepare for turkey season... I had not done that in years, so I agreed. Without thinking, I put that lightweight shotgun to my shoulder in a highly bladed stance, left straight down, gun held in a very relaxed manner. It was just force of habit, muscle memory... Ouch. It actually was worse than "ouch".
The point is, there are a lot of things that can be taken from competitive target shooting and applied to hunting, but there are some things that don't translate well. Stances like those pictured in the previous posts are an example... Any shooting technique that requires a specialized shooting jacket is another.
Jim
edit: Jimbob and I posted at the same time... and no surprise, we are saying the same thing.