Originally Posted by
Mike Blue
The idea of body fluids staining stain resistant steels is valid over hours, minutes on carbon steels. However, that very thin edge that does all the real work does not last more than minutes in a bloody living solution. Next time you're in the OR, see how often the surgeon asks for a new scalpel when cutting tissue. Human chemistry degrades the edge surprisingly quick and human skin is some tough stuff.
The idea of carbon vs stain resistant has been picked up in the culinary world too. Apparently the micro-pitting that occurs on carbon steels from food chemistry, not to mention that nasty black patina, is the perfect place to harbor bacteria that might cause an unsuspecting customer to have a cramp. As much as chefs prefer carbon, they are up against the bureaucrats in the health department when it comes to their tools.
Likely this same doctrine is why barbers had to give up use-more-than-once razors on their customers.
The "why" of carbon vs stain resistance has more variables than appear to the eye.