Well, um, with a modicum of footwork in this very forum, I seem to have found my answer.

From Guru Garym:
Except in this case, where I am using one folder with both artist and album names in its title, I would only use the TRIMFOLDER command once, not twice, to make sure only the album folder is carried over, like so:
[TRIMFIRSTFOLDER][origpath]\[origfilename][]
And don't forget the little [] at the end of this line. (For multiple TRIMFOLDER commands, you have to use more than one doule-bracket at the end.)
Sorry if I wasted anybody's time.
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