Funny, but no single specific key really seemed to emerge. It was kind of universally, democratically — um, tonal? Atonal? Ab-tonal?
Suffice it to say it was a doomed experiment, no surprise given my crappy piping.
On the flute I usually play it in C (or would that be one of those A minor or __ modal things?) – a fellow who comes to our session plays it fingerstyle on his guitar, so that’s what we picked up. It’s nice in Em/G too.
With the first downbeat on Cnat? That’s how I play it on flute. I think of it as an A-ish tune.
Hmm. In G, on the pipes (that is, with a Bb downbeat). A bit of keywork, but it might sit with the drones well that way. I must try that.
Another fave is Eanach Dhúin (Anachuin) on pipes, in G or D. D, mostly. In a moment of perversity I played that one for a yachters’ party. Sick, huh? 
I tend to think of it as A-mish 
as well. IIRC, that’s what Larry Nugent does it in before he rips into Down the Broom/The Gatehouse Maid, which makes sense and makes for a super set. Just as a note I think he does it all on an Eb flute, so that would make … argh, my head’s starting to hurt already.
Anyway, it’s one of my favorite recordings ever. 
OK, now we’re all curious about yacht party. What the … ?
The Silly Cow Milking Her Joke plays fine on the chanter (or flute) in whatever weird modal key it is of G (tune starts on A).
AB | c2 e2 c2 | B2 d2 B2 | (3ABA G2- | G2 etc.
To get it to play well with D drones you’d have to drop everything a full step to start on G. Dropping it down a full step means cross-fingering, or better yet, keys, to hit the Bb’s and Fnat’s cleanly. Using keys means your fingers don’t have to get cross, and we all know what happens when our fingers get cross with us. 
djm
Hey, I resemble that remark!
Thanks for the input on the playing of it pipewise, though. If I wasn’t so terribly spastic in the second octave things might not have been so bad …
I just gave the G transposition a quick run-over yesterday and that will be the end of it altogether; even with keys it doesn’t make things any more pipe-friendly. I’ll leave that exercise in finger-breaking to the geniuses.
The party was no big deal, just a gig for a get-together of sailboater-geeks at someone’s house celebrating their first flotilla or whatever it is of the year. It was cold and wet, and they’d gotten themselves up early to enjoy their clammy time on the lake. Freakin’ Minnesotans. Utterly mad.