Interesting discussion, which I think may never be resolved - lie so many concerning tune origins. However, a couple of small observations/questions. To my knowledge, the Bellharbour Ceili Band did not circulate to much in the 50s/60s. At that time, there were, at least, 15 ceili bands in Co. Clare, of which the Tulla, Kilfenora and Laichtin Naofa were probably the most popular. I suspect that their area of circulation was pretty much the north Clare area. My conversations with ceili band stalwarts from that period (Sean Reid, P. Joe Hayes, J. C. Talty, Martin Falsey, etc.) confirmed how difficult travel was - one of the main reasons for P. Joe Hayes and Paddy Canny asking Sean Reid to join the Tulla was that he had a car!
Yes, of course, musicians met but, remember, in the early 50s, the fleadhanna were only just getting under way. Robbie McMahon's famous song of the Ennis fleadh 1956, where he lists the musicians and singers who came from far and near, emphasises what an unusual event this was.
Fibnally, a question on Bulmer/Sharpley: was Volume 4 published in 1974? I was in Leeds from 1974 - 1977 (knew them both) and only remember volumes 1 - 2 in those days.