Maybe that should be Uncomfortable Safety. Or something else.
The techniques that fall under martial arts are basically heinous crimes except in a very narrow set of circumstances. We are playing at causing pain and suffering. You can choose to be mindless about that and see it as a fun hobby.
But if your students (or you) ever need to use it, it will be harsh and both emotionally and physically challenging. Uncomfortable. Can you be rude to a stranger? If you are reading this in a coffee shop, can you look up right now, pick someone at random and say, "You are ugly and stupid" and then go back to reading? If not, I submit that you will have an even harder time hitting a stranger. (And if your introspection muscles are fit, you can pick over your self-analysis of why you don't want to be rude to a stranger and find out some of the things that will freeze you in self-defense.)
Training for self-defense presents challenges, and some of those challenges border on contradictions. Just to name a few:
1) The people that need self-defense tend to be the ones least likely to seek it out. Being in denial of the existence of danger is one of the deep underlying factors of making people victims. If you are in denial of the problem, you have no reason to seek solutions.
2) The most effective stuff is the stuff that mimics the real thing. Which means it is hard and hurts and is scary. My sensei estimated that for every yudansha he promoted he had over 5000 start. Why so low? "Because jujutsu hurts, Rory. You can get a blackbelt other places in half the time and it doesn't hurt every day." And that means, again, that the people who most need it, the ones who are afraid of physical pain (and that's what predators want in a victim) try to find a safe, easy and painless way to learn about fear and pain.
3) The ones that seek out and enjoy intensity and contact tend to be a pretty specific demographic, and they have a specific vibe and they tend to get targeted for no more than a monkey dance and even then, only if they hang with immature people.
One of the biggest challenges, when you are teaching victim profiles, is managing their comfort zones. You must create a safe place to practice unsafe things. And you have to create a comfortable way to destroy comfort zones.
This is one of the reasons why SD has to be taught to individuals, not as a check-the-box program. Comfort means completely different things to different people. For the guys who came up through the contact martial arts, if they aren't nursing a serious injury, they're comfortable. For someone with no exposure, they tend not to even think of physical comfort but emotional comfort. There's no real pain in a sweaty, hairy guy holding you in a pin, but that is way outside the comfort zone of almost everybody who really needs this training. This is nothing to us, but a very big something to other people.
We're getting a generation of children who have been discouraged from rough-housing, who don't climb (and fall out of) trees like we did. Youngsters, these days... but seriously, we used to play mumplety peg (our version was a knife throwing game to see who could get closest to the other guy's foot) on school grounds.
They have to be taught, slowly and gently, from the ground up, how much fun it is to brawl. I still remember IM's wicked grin when she threw Steve-the-Gorilla. But it had taken a long time for IM to learn it was okay to clinch, throw, grapple and hit a person. And longer to think it was fun. But when she grasped the fun...
Which means they have to be successful. Not discouraged. Never punished for doing well. And as confidence increases... no scratch that. What the hell is confidence anyway except for a completely untestable faith that things will be okay? As the sense of fun increases, you increase the intensity. Until the student is doing things that would have been unimaginable in the beginning.
But, at some point, you have to overwhelm them. This is iffy. There are a few of us who love feeling overwhelmed. That feeling of too much information coming too fast and I can't understand it all-- that's become my signal that I'm on the edge of a great learning experience. Over the years, I've been conditioned to love that feeling because the reward at the end, the learning and insight is incredibly sweet. Friend Sam, when he started BJJ, described it as "The pleasure of drowning."
Some of us thrive on it, but very few beginners.
But it has to happen. Not every day. Rarely for some students. But all confidence is, in certain circumstances, false. Regardless of your physical monstrosity, your skills and weapons and anything else you want to name, there is stuff out there that can crush you like a bug on a windshield. Students (and teachers) need to be reminded of this. Because this is what keeps us humble and keeps us learning.
So you overwhelm them so that you can show them the next steps. So that they realize what they know, but also what they do not know. Overwhelm, but (with one exception) do not crush. There is a difference between overwhelmed and "there's no hope nothing works so why bother." A bad SD instructor can create an incredibly passive victim.
The exception? Almost never appropriate, but there are ways to force someone to face personal mortality in such a way that it causes some profound changes to their personality. Unfortunately, it crushes about 50% even of hand-picked, contact-experienced senior practitioners. The ones it doesn't crush get roughly an order of magnitude better.
The Baby Elephant Story
My lovely wife went to a karate camp years (decades now?) ago and they told her that students were like elephants. When you are raising an elephant in captivity, you chain the baby elephant's ankle. It struggles and pulls and can't break the chain. Once the baby elephant learns it can't break the chain, it quits trying, and you can immobilize a full grown elephant with a piece of string.
Your students will come to you with all kinds of bullshit beliefs about what they can't do. (The bullshit fantasies about what they can do tend to come from experienced martial artists.) Your job is to prove them wrong. It's not hard, but it has to be done carefully.