Wolf; to answer your question. The inertia of the blade is the same in both scenarios, with the blade moving and striking a stationary object, or a (previously)stationary object hitting the blade.
The total force in the second scenario is much greater, assuming we accelerate the workbench as fast as the knife was accelerated before striking the workbench, however, the limiting factor is the human arm which holds the knife. The arm will give way, and act much like a spring.
The force applied to the knife, is fairly close in both situations (although anyone trying to accelerate a workbench at the velocity at which a knife can be accelerated will quickly gain a real appreciation of how much force it takes to accelerate a significant mass).
There should be no significant difference in the action of the liner lock. Remember, inertia not only tends to keep stationary objects stationary, but also to keep moving objects in motion, so whether or not the knife moves is not pertinant.
Chris; I have read the knife tests on BFC, and several other tests as well. Further, I have spoken with A T Barr on more than one occasion, and own two of his knives. While people correctly adopt his test of liner lock stability, what most people do NOT understand is the great skill with which A T Barr fits everything on his knives, but most especially his liner locks. They lock up absolutely solidly, yet disengage effortlessly.
When you apply the A T Barr test to a less well fitted lock, it is unrealistic to expect the effect that Mr. Barr speaks of in his knives; 'mating' the two surfaces, tang and liner lock. With a less well fitted knife, you are usually dragging very soft, sticky Ti across a very hard, slick steel tang. Don't expect a few whacks to turn an indifferent lock into a masterpiece. Perform the test just to make sure your lock is functional.
Perform the test VERY carefully, and have some impenetrable substance between your hand and the blade of the knife you are testing. On the BFC tests, Spark had leather gloves on. This is inadequate protection, unless they had steel mesh inserts.
Please let me repeat my earlier statement: if your liner lock fails, it needs repair; by the factory or knifesmith who made it.
[This message has been edited by Walt Welch (edited 17 February 1999).]