Genesis,
I've compared military training to diving before, but always if I was comparing apples to apples. The allusion you used...Marines never leave anyone behind, and DIR philosophy of always sticking together simply does not work. It is like comparing apples to oranges.
Marines are in combat; cave divers are not. Marines never leave a man behind out of a code of life as a Marine instilled upon them. Every Marine that they serve with has been similarly trained. Dive buddies are a different story.
Marines risk their life, and risk their life saving their buddy out of a belief. If you have ever been there, you can understand, if you haven't, you cannot, nor can you comment on it. Diving is not that way, unless you're buddy is your brother or father or mother. THAT IS HOW STRONG THE BELIEF OF THE MARINES IS!! That's an assumption on my part, I was Army. I am assuming that their beliefs are at least as strong as mine were.
FYI, The no man left rule behind refers, usually to dead soldiers or Marines. Do not let the enemy take them away. This is simply not something that applies to diving. I'll be happy to expand on that with you, privately, if you want.
Choose carefully your analogies, Genesis.
Colin Berry