Hippocrates, the father of medicine, said that if you want to be a surgeon, go to war. He said that 2000 years ago, and it's just as true now. If you want to learn how to do this job, go to war, because the panoply of injuries is pretty much infinite, especially now with what modern weapons will do.
To address your question about the protective equipment, there is always a balance between firepower, mobility, and protection. You choose a mix of that and then you go into action. You might choose it right for that particular mission, or maybe you choose it wrong; there's no way of knowing ahead of time.
I can tell you that having slogged it out on patrols with that frag vest on me and the tac vest over top, I wouldn't want that thing to be any heavier. That would be about the limit.
It is very effective, and that's part of what we're seeing. We're seeing the effects of that in terms of the casualties.
Bill Kerr, in my hometown, is a guy I've been personally looking after for the past five years now. He is Canada's only triple amputee. He'd be dead as a doornail if it hadn't been for all the stuff he was wearing. So it's very effective armour, for sure.