Right, I will probably do it the way Barfly does it (using the V: field. I don't have a Mac so I can't run Barfly but I'll take your word for it ;-) It also won't be too hard to implement in the GUI, allowing you to combine voices from a list. I already support chord symbols directly before the notes but I like the idea of breaking up chords and notes for readability of the ABC file.
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