Thank you very much.
I had visited the NewerTech .pdf but not the lowendmac, yet. There’s also a varied and extensive examination here on the forum, which may explain why my query was was given a fairly wide berth (perhaps as if it were indeed “the plague”). Seems that the NewerTech 7447A variety can be problematic, compared to others.
(Yes, lazy me finally typed 7447A into the search feature here.)
However, given the current behavior of this particular QS (without the NewerTech installed), this 7447A may simply go back to the boneyard for now… or receive the ultra-special Jimi Hendrix lighter fluid treatment. Or I can find it again later, and Groundhog Day begins all over again.
Indeed, perhaps yet more evidence of my own synapses failing… still not remembering why the 7447A was in my boneyard in the first place.