Spaces not conditioned but within the envelope's air barrier and within the majority of the envelope's thermal insulation may be considered "indirectly conditioned"

I can say that I'd much rather have ductwork in an unconditioned basement (typical up north) than in an unconditioned attic (typical down south)

I wouldn't let duct considerations drive a decision whether or not to duplicate air seal / insulation

It is actually better (more polite) to post your own thread than to "hijack" another.

Thank you for the clarification, and for the hijack advise.  I will bear it in mind in future posts.