I'd call the reality-joint-cleaving line the one between adrenaline-trigger training and adrenaline control training.

That is an excellent point. My father and I still sometimes get into debates that pivot on this. He says that in a real fight your fight-or-flight system will kick in, so you might as well train tense and stupid since that's what you'll be when you need the skills. But I've found that it's possible to make the sphere of things that don't trigger the fight-or-flight system large enough to encompass most altercations I encounter; it's definitely the harder path, but it seems to have benefits outside of fighting skill as well.

A less discrete way to look at it adapts the No Free Lunch theorem...

Possibly! I think that in the end, what I most care about in my art is that I can defend myself and my family from the kinds of assaults that are most likely. I'm not likely to enter any MMA competitions anytime soon, so I'm pretty okay with the possibility that my survival skills can't compete with MMA-trained fighters in a formal ring.