A friend of mine lent me a book, Training at the Speed of Life, by Kenneth Murray, has been rather interesting. I mentioned it to a friend, but called it Speed Life, and I am pretty sure there's no book by that name. The google result showed nothing of interest anyway. So, back to the book:

In the intro alone, it mentions how different training scenarios which I am familiar with, have gone awry. One example was how the MILES system (which is laser based) incurred a casualty with live ammo, instead of blanks. Beyond the anecdotes however, is an altered state of consciousness required to train correctly.

Having something be real, is the only way to train as far as I am concerned. The book goes into the psychology of different encounters, rituals of safety, the reality basis of training, and a few other details. I think that the psychological aspect of the book has been the most interesting. It's important to understand the mechanics of the mind whenever trying to improve for a particular scenario, especially one which can be stressful and requires excellence.