Look at a good cutaway diagram of a whitetail, I'll bet at least nine out a ten bowhunters would draw the scapula in the wrong place. The only way you need to shoot through the shoulder BLADE on the way to the heart/lung is from a HIGH quartering ON shot, such as from a treestand with the deer almost facing you, nearly the worst angle shot you can take. I've shot THROUGH the shoulder on loads of animals, not the blade, the muscle. Including, bears, hogs, gemsbok, wildebeest and water buffalo. Arrows go through muscle easy, not so good through bone. I have made some VERY long tracking jobs on animals that were shot through the scapula, its because on a broadside animal the only thing behind the scapula is more bone and muscle. Most of what people call the "shoulder" is only soft tissue, Things got a lot easier when I started getting serious about animal anatomy.