"I was figuring something closer to breaking the minds of those who would later be psychologically conditioned into the proper warriors. Without their humanity intact they could change from people into tools."
That is exactly how the USMC shapes you, I'd try to be more unforgiving then my drill instructors. Part of the personal training I'd imagine I'd give. If you look at other honor bound, war-like societies like Feudal Japan you'll see shame and disgrace is considered a worse punishment than death. I'd imagine that would reinforce their loyalty.
"Ever read Fahrenheit 451?"
I have, interesting alternate reality in that book. The complete 180 in firefighters made it hard for me to become immersed in the book though.