A rattle bag? I dunno, Matthew. Doesn't sound like a bagpipe to me. Sounds like a medieval shakey egg.

I once saw a drawing from a medieval MS that showed a peasant playing a bagpipe and a devil holding up a hand to tell him to stop. So if it was a bagpipe that offended Dafydd so, he was not alone in hating it.

I will check out your links.