Another way of looking at this issue is to consider what we think of as traditional music. This is a definition posted by Diane Easby sometime ago and although it won't everybody it looks to me like it does the job:

'The tradition' comprises art forms of a distinctive national, ethnic or social group rooted in that community's lore and customs and passed on orally, aurally or by demonstration rather than by written/recorded or formal didactic means. It has thus belonged collectively to that community, rather than to individuals or the state, and tells the history of the people from their common experience.

In the case of music, its platform has been predominantly the informal social gathering, the workplace or the home rather than the theatrical stage or concert hall, and pieces tended to be known by what or who they were about rather than by composer. This is not, of course, to say that trad musicians have not borrowed and adapted from formal composers or from other cultures. Obviously they have, and do, which is why the tradition continues to evolve.

Where does this place the music of some current bands who have a deep understanding of musical theory, written and otherwise, and are not afraid to use it.

Before we all jump up and down let me restate - you hear it and you either like it or you don't but that is not my point. My point is how does this complex music relate to the oral tradition?