I am not that good at threading a needle so I do see shoulder damage almost every time. (meaning loss of my favorite stew meat).
As for the nervous tissue being carried throughout other parts of the body, well I have spent the last 2 hours looking for a cite for what I posted and I do not find anything. Back when the precautions were 1st coming out there was a lot of information given out that wasn't scientifically proven and that information isn't found today. But the precautions still exist that we shouldn't cut bone, don't touch brain and spinal tissue, eye's, glands, spleen etc. and head shot animals will make for hard to handle carcasses.