I'm grateful to Airy and Nige_S for their insights.
To Airy: yes, I have used the debugger, and it usually confirms what I am experiencing: the macro "hangs", "just sits there", "stalls" or whatever seemingly irritating description I use to describe the point of fail.
To Airy and Nige: I went for the President Musk option and defenestrated the macro. Perhaps it was carrying with it some bad juju from the macros it was borne of via duplication?
FYI: prior to recreating the macro from scratch, I reindexed Apple Mail and a host of other perfunctory directory structure and permissions housekeeping, rebooted from a FULL SHUT DOWN (which our engineers advise, as a RESTART apparently keeps debris "alive" in RAM).
Upon recreation of ostensibly the same macro (atttached), everything is back to behaving as it should (as much as I can tell).
I still "see" the macro steps taking place in the menu, etcetera, but they are "behind the scenes", and the pull-down menus no longer make unwanted appearances (quite a mess of cascading folders).
I reiterate my appreciation for the collective insights.
Paul
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