Okay, I know this topic gets worn out on here, but I'm interested in getting some more information on something. I have a Magna-Matic sharpener and try to replicate as closely as possible the factory edge on the OE blades I use. In other words, I sharpen the blade to somewhat less than razor sharp. I think most of us are aware that if you overheat a blade during the grinding process to the point of discoloring the metal, you have removed the temper, and the blade won't hold an edge as long. I also realize quenching the blade in cool water can help reduce the likelihood of this happening. My question is, for those knowledgable on the subject, is there any benefit from quenching even if you don't have a problem with heating the edge to the point of discoloration? In other words, does the heat produced from grinding soften the metal over time even at lower temperatures? It seems to me that as my blades get more worn, they don't hold an edge as well, and get more nicks and dings than newer blades. This observation isn't scientific. I've never tried to keep track of the hours etc, not sure if it would be possible anyway due to the wide range of conditions the blades encounter on a daily basis, but it just seems to me like my blades that are close to the end of their useful life tend to need changing out more often than blades I've just put into service. Thanks for any input.