Mike,

I suppose its important to some people to come up with these sort of definitions, so good luck with your work. Personally I'd rather just play and listen to the music.

I presume if your invoved in this that you know about the Irish Traditional Music Archive (www.itma.ie) and Comhaltas Ceoiltoiri Eireann (www.comhaltas.com), who will probably have some working definition of what they consider constitutes Irish Traditional Music on their websites.