Myth disputed, the fruit of my research, a clearly defined temper line (see arrows, the light line) in the CPM S30V stainless blade. This is going to stir some controversy within the knife community and beyond. For further reading please see Blade Magazine February Issue 2004, page 122. Please click for article in pdf fomat. Note: Image has to be scanned dark, so the temper line is visible.
This knife on the right was sectioned and a microanalysis performed by SAMAC Engineering Ltd. This blade is the 3rd differential heat treated stainless knife I have done and it has a "run away" temper line. Just above the white arrows is the temper line on the blade (whitish line), which might not be readily visible on all monitors. I like to thank Jonathan P. McGovern, Microscopy and Image Analysis Consultants & SAMAC Engineering LTD. for there contributions.
(Main Image, Bladegallery.com)