With several of my coated Bussekin blades I have found that the edge is not actually ground in deep enough to reach the actual heat treated layer of steel with all of it's properties. If your edge is say .005" away from that level, a good resharpening can make a world of difference if it takes you into the properly treated layer. I don't know if there is a way to even see it at the point of sharpening at the factory since I can't see it when I sharpen, <img src="/ubbthreads/images/graemlins/confused.gif" alt="" /> but I do know the performance difference between the right depth of sharpening and not is night and day. The outer heat treat layer can be slightly brittle and easy to dull, more with SR101 than INFI, but INFI will dent/roll pretty easy in that layer. Just my personal experience with having used 30+ different Wauseon blades.

Satin blades require grinding below those layers to get rid of the dimples/imperfections, so the chances of the edge being stronger have been pretty good. <img src="/ubbthreads/images/graemlins/thumbup.gif" alt="" />

I have a theory that different batches, or locations within a batch yield different results as well, but it's just an educated guess from my user experience.