I entirely agree that accessibility is a primary definition of traditional music(or folk music). But not necessarily accessibility to everyone. On Saturday night I was playing in a remote(but not ridiculously remote) country pub for a Paddy's night do. Gypsy step dancing and general mayhem was happening, entirely informally. Definitely traditional, but not I think acceptable either to a mainstream Saturday night town pub, or to the Smooth Operations/Cambridge Folk Festival world either. And certainly absolutely nothing to do with the Leonard/Lakeman concept of tradition. It was a pissup with gypsies, and others, dancing to fiddle and accordion and banjo, pure and simple.