If you try to escape the lockdown by just spazzing out like an idiot, you may pop a joint. The same is true of knee bars, arm bars, shoulder locks, guillotines, and all kinds of other things everyone does. When you're caught in a lockdown you can't disrespect the danger you're in; when people want to ban it, I tend to think it's because they don't *want* to respect it. They don't want to be noobs with regard to it. They don't want to have to learn something they suck at. Even though it's perfectly possible to train it safely with a modicum of understanding. Kinda like TKD and head punches.
It's the first step into McDojo country. I wouldn't go to a place like that long-term.