True, but by the rules, without me retconning anything, only outsiders can really master the nine swords styles properly.  (dragons and elementals can get close, but they don't have the proper anatomy)  This strongly suggests a supernatural origin, and I'd simply prefer that nine swords combat styles were mystical and exotic rather than mundane.  (since fighters and warriors are assumed to still be in the majority, at least among human)<br/><br/>There ARE a lot of concepts and ways to interpret the nine swords styles, but you can't get away from the fact that they're explicitly not just hitting someone in the face really hard.  That's the power attack feat.  Striking with such speed that your blade strikes two foes, or hurling an opponent through the air with the force of a single blow (some of the least overtly supernatural things a nine swords fighter can do) go beyond just training a whole lot with a sword; they're blatantly superhuman efforts.<br/><br/>(now of course, they fit in pretty good with the game mechanics, which is good because the 3rd edition rules were originally designed to describe human like characters within a reasonable range of human ability, rather than to try and create a good game.)