Stev0 wrote:
Non-piper here, but just wanna say... Is there something special about the instrument that would prevent it? People improvise new songs all the time on every instrument under the sun.
-edit... sorry to say that like a butthead, I'd be thrilled to hear anyone writing a new song live, it's not an easy thing to do.
There isn't anything about the operation of the instrument that would preclude improvisation. But In the idiom of Irish traditional music it simply is not commonplace to improvise melody lines on the spot, as you find so much in free-form jazz or blues jams.
In a trad session with other musicians, you play pieces that the group knows. There is room for expression in the ornamentation and phrasing, but this is to enhance and embellish the basic melody rather than alter it. Alterations would throw off the other players.
If performing solo, there may be a bit more opportunity to noodle around. But straying too far from the structure and melody line of an actual tune could leave the audience scratching their heads.
Anyway, in this video Chris McMullan starts with some slow improvisation. He doesn't dwell on it too long, but soon leads into the slip jig "The Choice Wife":
https://www.youtube.com/watch?v=N2v2uvjxC3w