I think some clarification of definition might help. This is just my opinion, of course. I’ll try to include some history for the “younger afi’s”. No doubt some will disagree with me. That's ok. My credentials are sound.
The first “Hard Use” production folder was probably Al Buck’s “110” in the mid 60’s.
The intent was to create a folding knife that could take on many of the pressures put on a fixed blade knife but be easier to carry. The knife had the ability to cut harder to cut materials and deal with difficult environments. The blade was thicker than “normal” folders, (fairly fine tip though). The lock was strong and exceptional steel (stainless 440C) was used to be able to cut the harder to cut materials. Pete Gerber followed with his folders, also made with exceptional steel. Al Mar began producing hard use knives with exceptional steels. Al also had a military background which influenced his designs.
Chris Reeve and Spyderco made hard use folders in the early 80’s. They were using better steels, strong locks and tough handles, many of these earlier hard use folders are still in service. In the mid 80’s a number of companies also began producing knives intended to go through tougher materials.
(“Hard use” is a marketing term that was created far later than the designs. The same is true of “tactical”

.
Chris was using Titanium for his handles and he invented a new type of lock which proved to take impact well. The Reeve Integral Lock (often called a “frame-lock”

has “enjoyed” much attention. These were designed and built for hard use.
Then along comes Mick Strider. Here we have a knuckle dragging knife maker making knives for knuckle draggers. That sounds good to me. He said; What if I have to abuse my knife. What if I have to pry with it, or twist or dig, maybe hammer? Prying, digging and hammering with a knife is no longer “hard use”, it is “abuse”. Mick’s knives were made for abuse.
Another knuckle dragger, Ken onion, chimed in with the ZT line. Again, the knives were designed and built for abuse. Lynn Thompson was another that creates knives to be abused. First he made fixed blades and later with folders. These were also designed and built to take abuse.
It is interesting to note that some of these designers paid special attention to using exceptional steels. They usually used the best steels available at the time. They also used edge geometries that were more abuse friendly. The theory being; if you are going to pry, dig and hammer with your knife, these activities are very hard on the edge and once the edge is gone, what you have left is a folding club. Generally, exceptional steel will perform better and last longer.
I question the theory that a “lesser” steel can be easily sharpened. If you are not carrying a pry-bar, a shovel, or a hammer, you are not likely carrying a sharpening stone.
With that in mind, our Military model was designed to be a light weight, strong cutting tool and I guarantee it will poke and cut with the best of the “hard use” and “abuse” folders, and probably better. It was not designed or built for abuse.
We have had many of our troops write to us thanking us for making the model that saved their booty when needed. They had it with them because it was light weight and easy to carry. When we create a knife for our troops, law enforcement or emergency personnel (SAS – Save And Serve), we are very serious about cutting performance and reliability.
Perhaps some think that there is only one way to design and build a knife? Or that their definition of usage is the only one there is? Perhaps they can show me the knives they’ve designed and produced and we can discuss the merits and drawbacks of their design? There are ALWAYS trade-offs in design. Weight, performance, price, etc.
I will say that there seems to be a growing demand for folding abuse knives and we have several on the drawing board. They are being designed and built to take abuse. But they will not likely be able to cut and poke with the efficiency of the thinner Military blade nor will they be as light.
Just some thoughts to share.
sal