I was browsing through FMC today and ran into that creatively explained rule again and was like "I'm sure I've asked about this somewhere, but why is it still unclear now?"
Because I'd forgotten about asking and never saw Marcia's answer, is why!
So please accept my apologies for my short attention span as well as my thanks for explaining, Marcia. And again, thanks for gifting us FMC. OD&D is a fascinating artefact and you've been doing great work to help us make use of it.