Nobody in this century has ever tested a sword. Few in the last century. What would happen if a 19th century sword of the finest Toledo steel met edge to edge with the finest Katana from a Japanese master? Nobody knows. What would happen if the finest sword in Wootz steel, capable of slicing a falling silk scarf, met edge to edge with a sword in a modern, high quality stainess steel, crafted by a gifted maker? Nobody knows. I've pondered this very subject for many wakeful hours and never came up with an answer. If Mr. Cashen is correct, you could never say if 6 were enough. The Spartans at Thermopylae fought for three days with bronze swords. The Romans conquered the world with iron swords. Medieval swords of unknown steel hammered on swords and armor for hours and seldom failed. 19th century cavalry swords of questionable steel met sword to sword at closing speeds of 20+mph and survived. I'm sure a sword in D2 made my a competent knifemaker would do fine. At the end of the day, it's really more about what's at the other end of the sword (or a knife for that matter) than what's at the point - and who made whatever it is of whatever steel, and how well they did it.
My opinion, anyway,