You need to be flexible to shoot in ANY position. If you're a target shooter than pick one and go with it, I suppose, but in hunting situations, you better be able to shoot open stance, close stance, on your knees, all bent over and crunched up, off to one side ......... I watched a Fred Bear shot on a video and he only 3/4 drew the bow on a fast walking muley buck - but because he had shot so often like that I imagine, the arrow went where his mind/body told it to go.

That said, when I practice, I shoot more of a square stance I think, I don't hunch over, I don't push/pull like Asbell does, I shoot more target style I imagine than anything.