[I "are" old...
I don't own a locking knife, or one with a clip
EDC is a Vic Classic SD.
I still prefer a simple screwdriver, or carton cutter that takes a single edge razor blade.
Just...me, and I how I come up and all...]
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I think Steve put it about right for.
Since my edc folder is usually a Victorinox bantam or Case peanut, with a classic as back up on my keyring, it's not a very strong chance I'd be using a knife for defense. To slow to get out and open. The only lockblade knives I own are a Gerber LST as my lightweight beater knife, and a couple of Opinels in different sizes.
It's funny, but I used to carry a knife for defense when I was a young man, a very long time ago, but after about middle age, I stopped. I now preffer a nice screwdriver in a pocket size, or a box cutter. I like box cutters, nice and flat, doesn't get in the way of my edc pocket knife, and cheap enough that I can use it for stuff I don't want to ruin the edge of my nice Case on. Like stripping wire, scraping a battery terminal. Easy to replace the blade.
I just don't think of a knife as a good weapon anymore, too many other things to use. Besides, I have my blackthorn stick when out in public, and that seems to work better.
As for choke holds, if somebody needs a knife to get out of one, they need to go get some training.