FWIW, I find it helpful to NOT think of those ACE BDF patterns as arpeggios (even though they are). One other thing I can hear that might work there, at least for practicing slowly, is a tight Cde or def piping triplet, ala A(3cde) A(3cde) B(3def) B(3def). I would be cautious with those, though -- until you can get them really, really tight, which takes ages of practice, especially on the flute -- they can be dangerous to your rhythm.
Anyway, I think the real problem is that lots of people play it crazy-fast. My theory is that "Fiddlesticks" infected a few fiddlers, and the speed disease has just spread from there. Sort of like the dreaded "Tam Lin." <meh> People tend to rush on upward patterns to start with; add a few frantic flutes and weekend-warrior rhythm players and it's off to the races. And like Peter says (and the Frankie/Mairead recording shows), it's a nice enough tune when it's played with bounce instead of as a rushing torrent of notes.
The Fiddlesticks recording I'm referring to is in the Track 15 set here: http://www.amazon.com/Irish-Traditional ... B0000037EC and even though this part is the Jig of Slurs, you can tell the pace is pretty bright to start with.
But at the end of the day, since it isn't quite as much of an ergonomic nightmare on even the D whistle, maybe just make it one of your whistle tunes. I kind of have, and I like its character on the whistle more anyway; it gets a bit cute and bippety. If you want to sidestep the G# in that "walk up" that a lot of people worry about in the 3rd part, you could try BCd ~ee (short roll)_e ... or BCd ~ee_d, or a short e roll with a breath (~ee'), or even a clipped long roll on the e (BCd eee') with room for a breath (that's the ') before the next a. I'm sans whistle at the moment, but I think I usually do a short-e-roll-breath-d combo there.
Or, of course, you could just develop the world's loveliest marchy bouncy version of it and see if you can cure your session-mates. Maybe it'll catch on and you'll have done a favor for all tunekind.
Sorry for the rambles! I'll go away now. Good luck!
That would be precious for me and the future generations of frustrated flute players 
(well spotted, Hans). I borrowed and adapted Cathy's ABC and missed that - alterred it in the B music but not the C music. Sorry! Have edited it now. I don't ever play it that way, nor can recall hearing it thus.
