He's not talking about what most people would consider diversity.
From just the first dozen minutes or so, he's essentially likening his
experience in the military, which was a functioning multicultural community, in essence, with failed community in a permacultural context.
I don't know why he's phrased it the way he has, because his message is more along the lines of, "Gee, I wish everyone was on the same permacultural page as I am."
The problem I see is where he's on page, say, thirty-one, and I am on page three-sixty-one. Or vice versa, but you get the point.
If the scope of my system and planning is radically different from his conception of what could be, my logic could be batshit insanity by comparison, simply because he lacks the conceptual permacultural building blocks to see as far. It all goes back to the Wheaton Eco-scale argument. A level two is much better than zero, and four is way better, but the logic of a six or an eight might seem very strange to a four, and incomprehensibly crazy to a two.
He's essentially saying that dealing with other ways of doing causes drama, and that drama isn't worth the benefits of working in community.
I think that the reason his military experience was effective in getting individuals from different backgrounds to accomplish shared goals is because they went through the same training and were taught to think in the same way.
He's essentially talking about a monocrop of thought. All it takes is a problem out-of-the-box
enough for their training to not apply, and that's one crop that won't survive to harvest.
What he's saying is worse than wrongly discriminating against people based on ethnicity, gender, or background, in my opinion, although not malicious, from what I can tell.
I think what he's getting at is that he'd like a permacultural melting pot. I don't agree.
I think that respect for the individual is all the socio-cultural lubrication we need; if things get sticky, apply liberal, even gratuitous quantities of respect for the individual and find out where the disagreement lies, and what the reasons for it are. Sussing out these issues often leads to the solution of many other interrelated sticking points.
I don't think it's a good idea to militarise permacultural training, or dogmaticise it. That involves the punishment of "wrong" ideas. If you can't do so with reason and respect, you're only creating more problems with adherence to code and punishments.
-CK
A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.
-Robert A. Heinlein