That’s interesting theory. I know some of the other things I’ve done over the years are on that spectrum so it’s possible.
I think there is a world of difference between biting your nails, which does you no harm, and deliberately cutting or wounding yourself in other ways.
Nail biting does harm T perhaps you don’t do it as much as most people, if you can control how and when you do it always washing hands etc that’s not an out of control habit, that’s a premeditated act. Completely different.
Admittedly I don’t do it all the time, just as soon as they start to grow again.
So not the same as most people. You make a choice. If we all made a choice we could all stop easily just make the choice not to.