That's what I'm saying, too
He has its own way of doing things. I would do the same? Probably not.
But what I ask my self is "if, for whatever reason he may have, he military sticks to a given exposure triangle, but wants more DoF, what is the solution?"; and the answer I give myself is "if you don't want to change any other parameter, then the only solution is using a wider lens and/or a smaller format, which are the only way, given that triangle you don't want to change, to obtain more DoF compared to a FF setting".
You would of course alter perspective, DR, SNR, etc, it's a fact; but still, if he doesn't care? Then good for him.
I'm not going to question why he does his stuff, unless his stuff leads him to shoot badly exposed photo; but his stuff works, he gets same exposure not altering the triangle, and gets more DoF. So why bother trying to explain him maths? He doesn't care about maths, because what he does already works.