Ron I really don?t see your point about folding knives without a lock being dangerous, they are designed to be cutting knives. If you?re using them for sticking (as into skin) then yes the blade on the cheap and cheerful ones will fold up on you. But they ain?t designed for that!
If because the person using them can?t keep the blade sharp enough to cut through the underbelly of a fish without out stabbing into it, then I suggest they learn to sharpen a knife properly so it does.
In 20+ years in the slaughtering industry, I nor anyone else who worked in that industry need to stab hide to break open a carcase. It was and still is done by cutting using the full length of the blade.
The only time you needed to ?stick? a knife in was and is, when bleeding an animal, and those are purpose made specialist knives for the job.
I?ve had a Swiss army knife (a real one, Victronox, not a Jap crap one) for over 20 years, I?ve used it for every thing from skinning to wood whittling and never had the blade close on me ever. One occasion and to prove a point, I used it to dress and butcher a whole pig.
?Kai is one such company? As for their butchery and slaughtering knives they?re shite Ron! As were all the Jap knives. Only two companies made consistent quality knives - Tailors Sheffield and Victronox Switzerland.