I think the issue is definitely worth discussing, and there are many things to be said about this.
One item is the definition of a knock off.
Let's take the Benchmade Stryker. It retails for $125. It has a liner lock, G-10 handles, 154CM blade. It is a decent tactical knife. If another company makes a knife that resembles the Stryker same shape, size, liner lock, ecxept the blade is maybe 440A, and the handles are aluminum, the liners would probably be some cheap stainless steel... maybe the knives are made in China... and the knife sells for, lets say $17. Is this a knock off? Whoever made this knife saw the Stryker and said to himself, "that is a good knife design, I can do that in China". Well, few "knife people" would go to a knife store and debate between buying a knife for $125 or $17. He (or she, or whatever) already has his mind made up as to what his limit is. Maybe its $125 or $150, or $180... but it is not maybe $10, or $30, or $125.
Is that a knock off or not, well, I think it is. What are some other words for it? Maybe it is an "imitation", maybe it is a "copy", maybe it is a "knock off". I think "cheap imitation", or "cheap knock off" are the best terms for it. As far as I can reason, it does not affect the income of Benchmade that much, because any Benchamde user or perspective user is not going to be seduced away from Benchmade for a knife that goes for $17 or thereabouts.
Now, if someone comes along and makes a knife that has the same shape, size, liner lock, maybe the handles are Aluminum or perhaps Zytel, or maybe even G-10... but something that is done with quality, and the knife holds its own as a quality tactical knife that is up to par with the Stryker, and it sells for maybe $85 or $100... well, that can be an imitation which Benchmade would have to worry about. Many people looking for something along the lines of a Stryker would be attracted to this other knife... if the quality is comparable, and the price is close enough to make people believe that the quality is comparable. Maybe these knives are made in Japan (as is Spyderco) or maybe they are made in Tawain (as is CRKT)... these are the companies who have the greatest potential for disturbing the business of good American knife companies... companies that can produce a knife of decent quality for a price that is less than the standard elite knives, note, not "a fractio of the cost" but just enough under the price as to attract some of their clientele.
The other day I was in a store and saw a knife made by a co. called RUKO. It was, dimensionally, a knife that was almost exactly like the Emerson CQC7. I think the price was maybe as high as $20. I asked the clerk about it, and he said that all RUKO makes is junk knives which they copy from other companies. When I picked it up, I could tell it was junk. Is Ruko in the wrong? Yes, because they are profiting off of Emerson's design. Is it hurting Emerson's reputation or profits, probably not. Nobody would buy a Ruko INSTEAD of a CQC7. Many cheapskates might buy it because they saw the CQC7 and thought it was cool, but didn't want to spend the money. Well, there is a spot in the market for crappy (krappy?) knives, and someone is going to make them, but they should come up with their own designs.
Designs and mechanisms that are patented are a special category. They should be punished, because that is what the law is for. The people making the knock offs are definitely in the wrong, because the customers are benifitting from a SPECIFIC funtion or mechanism without giving the inventor due compensation.
-Benchmade AXIS lock
-Emerson Wave opening
For example are two innovations that are patented. Even if someone is low enough to stoop to copying the design of a knife, the customer is going to find a knife design that more or less suits him well enough (don't get me wrong, I am not sanctioning the copy), but to give the customer the ease of a wave opening, or the specific advantages of an AXIS lock without compensating those who respectively invented them raises the stakes of the imitation and the security of the finances of each company. If a customer wants a WAVE, he had better fork out $150 - $200 for the Emerson, because only Emerson can give it to him, and if anybody else were to make it without authorization, that can hurt Emerson's finances drastically.
In short, copiers should be shot at... some at closer range than others.