The knife will stay tighter longer and not develop play that comes from wear. Impervium has about twice the yield strength of 304 Stainless. MS-60 work hardens readily and will get harder as it is worked. The knife will get better the more it is used. It has an entirely different name because it is a considerably different alloy.
Cold reduction is a forging operation.
The area in cross section of the rod has been reduced from 0.306 sq. You are beating on it hard enough and long enough to re-arrange the crystalline structure. It gets packed much tighter. Obviously this is a very long and expensive process. Lubricium is several times the cost of MS-60 and is hard to get.