I thought the metal tree was interesting. Yeah, mistakes, or maybe just difference of opinion. The other thing in a couple of the tree "branches" was it seemed they were not chronological. Like some bands from the 80's were lumped in with bands from the late 90's, how could they both be originators of a particular style of metal? Or maybe I was just reading the tree wrong. Anyways, stuff like that always give you something to talk about.