Since Cornish bagpipes(and their repertoire) have been extinct for some considerable time, all reconstructions are tentative at best, Like the pronunciation used in current attempts to revive the language. I speak as a good old Cornish boy who is a teensy bit sceptical of some of the wilder fringes of kilt-wearing Cornish Celticdom.
   Possibly the total extinction of the pipes and their music was something to do with this St Piran's Day recntly revived custom of piping walkers over a cliff?