@ Gordon - I don’t think I said what you said I said… I haven’t gone back to check, but what I certainly said initially was that there was “no such thing” and pretty much left it at that. I subsequently agreed with others who set out the historical perspective and processes which were the basis of my bald statement. I do not think that keyed flutes are “the definition” of the concept of an “Irish flute”. I do not, still, think there is really any such thing, notwithstanding the modern (post 1970) retro-development of keyless diatonic flutes more-or-less specifically for ITM uses. I have written about this previously.
My current opinion is that such keyless flutes, initially developed as cheap (and maybe better in tune for modern standards, though lacking keys, that is difficult if not impossible to achieve!) alternatives to expensive, scarce or otherwise unsatisfactory period keyed flutes, reflecting basic economics, developing skills of emerging makers and, yes, the relatively small need for chromaticism in ITM. Regardless of what flutes in what condition the “old geezers” may have played and in what style/with what techniques, I think that since such keyless flutes became a significant proportion of the flutes in use a modern playing style both based upon exploring and limited by them has developed to a considerable extent in the last 15 years or so. Sure, this reflects in many ways how the old geezers played who actually denuded their antique flutes of keys for whatever reasons (not working, lost, fat fingers, etc etc.) or who simply ignored the keys, but I think it has gone beyond that. I also think that there has developed a rather Luddite attitude in some quarters that perhaps seeks to ignore or deny the actual historic origins (so far as we can determine them) of the use of the flute in ITM and the actual instruments predominantly used pre c 1980, almost rejecting the use of keys as “un-Irish”!
Bottom line? IMO there’s no such thing as an “Irish Flute” or “Celtic Flute”, “real” or otherwise, in sensibly used typological terms. (Of course a flute physically made in Ireland is Irish, even if it’s a Bohm flute!) The term is out there, market dominant and we have to live with it, but we don’t have to like or accept it. I certainly object to both antique keyed, conoid-bodied, wooden flutes and modern replicas of them being called “Irish” - they are correctly termed Simple System flutes. Modern retro keyless flutes whose design is derived from the bodies of those mid-C19th Simple System classical flutes are… what they are. I think of 'em as “naked flutes”! 
We play Irish (and other trad) music on these flutes, and they may be especially well suited to it in a circular feedback stylistic process (and that is an analysis, not a derogatory comment). The instruments themselves, even if made in Ireland, are not typologically Irish - or at least, no more so than Bohm flutes made in early C20th England to suit the demands of the then English aesthetic were “English” and the French or American ones made for slightly different aesthetics “belonged” to those nationalities - they were still Bohm Flutes. The same could be said about national styles of Simple System flutes. These modern keyless ones are just flutes, part of the broad spectrum of the Western transverse flute family, in a particular form at a particular time, for a particular market. In this case that market may be primarily one of ITM players, but it certainly isn’t exclusively so, nor is it limited to Ireland or the diaspora of the Irish.
Any flute used to play ITM in a tolerably convincingly tradition-reflecting style will serve if the player knows what they are trying to achieve and how to achieve it on that particular instrument.
I also disagree that I play my 8-key flutes in a C/classical way - I do occasionally play bits of Baroque and Classical music on them, most “inauthentically”, but not with proper, fully developed classical flute technique - I have not the training nor have I done the hard work for that. I am primarily a traddie. Not, I fully acknowledge, one brought up in the living tradition or with a distinct or recognisable Irish regional style - I equally lack the background for that; but most of my influences are authentic trad and I use chiefly trad techniques in my playing, though I do also bring in bits from my knowledge of other approaches and from my technical understanding of the instrument - no more so, and indeed probably less, than a good many players at the forefront of modern ITM fluting.
Doug, the bad news is that Franz Kafka worked for the Czech Post Office. 
