To me it looked like Duncan was going for hurt rather than kill. Anytime things actually got to killing, he backed away on numerous occasions. He ran away to Paris from Joe, and he ran away from Methos twice so he wouldn't have to kill him. Which is pretty awesome.

I love that "Duncan MacLeod of the Clan MacLeod" is a kind of mantra with him. That he is a perfectionist about it. :) That Methos is able to snap him out with his name and his clan colors, and his sword. <3