I agree. It seems impossible that its referring to support staff in those numbers. I had heard of similar studies in the British Army in ww1, with similar results (training on man-shaped targets etc) - surely the army would be unlikely to change tack based on a study with such an obviously flawed conclusion.

Not to mention the fact that this was a time of much more serious discipline issues. People were executed for desertion, and despite that many people did. There was also much malingering, up to and including literally shooting oneself in the foot. Is it so hard to believe that some people just hid when battles came?

Id be very surprised to hear from the other person that by Vietnam they had gotten it up to 95% though. My impression was that the most effective move away from this sort of thing was the move to a professional volunteer army, no conscription.