I had a friend in grade school in the '60s who had one in his pocket when he fell off the monkey bars. It opened up on impact.

Getting it out of his pocket involved take his pants at least partially off.

He wasn't cut too badly.

Here in Ohio, I don't carry a knife for self-defense, as carrying one big enough for that purpose is WAY more hassle than just carrying a handgun.

In Ohio, unlike firearms laws, which are preempted at the state level, every little podunk town can have its own knife carry laws. You can be legal, walk across the street, and become a criminal.

There's FAR less legal danger for me to carry a registered MACHINE PISTOL here than a decent knife.