courtesy accidentals

I agree that normally, I like to spell things correctly even in transposed parts. But in the jazz world, it's pretty common to have pieces sight read on the gig, and sometimes a bit of judicious respelling really does make a difference in reducing reading errors, even if my example wasn't the most convincing. When sightreading, I find that even professional musicians can benefit from simplifications that reduce the number of less-familiar accidentals. Also copious use of courtesy accidentals, so I'm a heavy user of those, and that's why I consider the unrequested deletion of courtesy accidentals on transposition to be the single most critical bug in 1.0 and the single most important reason to have a bug fix release.

But, back to enharmonic spelling. I would note that while playing in the key of E might be common in the classical world, it's practically unheard of in jazz. There's a definitely "flat" bias in jazz, because of the predominance of Bb and Eb instruments. Not that Fb is common as a key, but not all E chords occur in keys in which E is diatonic. A number of the E chords that occur in jazz *are* actually more correctly spelled as Fb chords. For example, progressions in which E7 is serving as a tritone substitute for the V chord Bb7 in the key of Eb is a *very* common situation). In the key of Eb, the E7 spelling in concert key is actually just a convenient (and very much appreciated) enharmonic respelling of Fb for the sake of readability, but Gb7 is the far better spelling for that same chord in that same context in the key of F. So there's one very common situation that practically begs for different spellings concert versus transposed. Readability depends on familiarity, and it's pretty much universal that the progression in question would be spelled E7-Eb in the key of Eb but Gb7-F in the key of F. Jazz chord progressions often contain other similar cases - enharmonically ambiguous chords for which the better spelling depends on the key.

Also, most of the music where I actually care about doing this is not tonal at all, so there isn't necessarily a "correct" spelling from a harmonic perspective - it's just a matter of what spelling one perceives to be more readable. The guidelines like that says to use sharps in ascending lines and flats in descending lines because that usually reduces the number of subsequent natural signs required is fine for what it is. But depending on the specific line and the specific "key", sometimes that rule of thumb actually results in a line requiring *more* accidentals than a more individually considered approach that really examines the context and tries to optimize the line for readability. The more highly chromatic the music, the more likely this is to be true.

But you are absolutely right that the automatic "pitch spell" function isn't likely to achieve this. At most, I tend to use something like that as a rough cut to produce a simplification of a line that I can see will demand man changes, but really, more important to me is to have a single-key "respell note" command that works in note entry mode to then fix the line up further. Still, the automatic respell could indeed be more useful for MIDI.

Ideally the "pitch spell selection" and the respell-single-note-within-note-entry would both work as I suggested - specifically, applying the respell only to the transposed mode if invoked while in that mode, but applying it "for real" if invoked while in concert mode. Lacking this feature, I'm forced to make a choice between readability in the part and accuracy in the score, and I'll choose readability in the part every time, but I'd rather have both.

And I do agree that having spelling be consistent - and hence controllable and predictable - between concert and transposed is a huge improvement over the way things apparently were in previous releases where notes were respelled on a whim. I'm just looking for *additional* control, to get different spellings between concert and transposed when I aks for it.