Peter Duggan wrote:So define 'written'...
If I play Calum's Road (as I've been doing for 20+ years) in its original D key on an A whistle using DrPhill's 'G fingering' but without transposing the tune on paper, computer screen or whatever, then I'm not transposing but simply playing it in the original D. If, OTOH, someone else is writing out the tune in G before doing the same, they're treating their A whistle as a transposing instrument (in classical terminology, a whistle in G!) to sound in the same original key. So perhaps we'd need to use two separate terms (eg 'pitch transposition' and 'finger transposition') to be absolutely unambiguous here, although 'finger transposition' also conjures up the delightful vision of swapping the fingers you've already got from knuckle to knuckle!
I suggest that instead of talking about "D whistle G fingering on a Bb whistle" and so on, we should really be talking about dominant, subdominant and tonic fingering, so it applies to all whistles without confusion as to which keys we're talking about. So you play Calum's Road on an A whistle using subdominant fingering, and it sounds in D. Simple.
Or you could call it tonic, up (dominant) and down (subdominant) fingering. I think it would simplify the discussion. Anyway, just an idea.