drewr ... Just to be clear, and to address your main concern ...
As far as I know, the ABC spec itself doesn't require time value checking. I don't know about MuseScore, but abcm2ps - which is more or less the reference standard for ABC rendering - freely allows you to violate the time signature; in effect, it assumes you know what you're doing.

This makes it easy to notate free-form slow airs, or crooked tunes, etc. You can also specify time signature = none if you like.
As for the personal shorthand you've developed ... You can certainly re-purpose the standard symbolic inventory of ABC however you like. I do this in my own detailed transcriptions in re-purposing mordents, bow markings, etc. But the ABC inventory is more limited than something like Sibelius, so you might have to experiment with modifying your idiosyncratic conventions.
drewr wrote:
I'll try the analog paper method and who knows I might like it. The problem I forsee is that I do A LOT of revisions as I gradually perfect my interpretation of the tune I'm learning. Better get myself a good eraser.
You might want to look at my "Music Pencils" thread here:
viewtopic.php?f=43&t=85646I'm still experimenting, but having good luck with mainly the 2B/4B pencil combination ... and a nice polymer eraser.

I definitely don't see manual notation and software notation as incompatible, any more than a good penmanship hand and a good word processor. But I'll admit I do my trad transcription directly in ABC for the most part, whether on paper or in my text editor.
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