That did it - thank you!
With an increasingly decreasing number of keyboard shortcuts available it’s been useful to me that the Control prefix is usually available for purposes, e.g. Services and Script menu functions.
Maybe with a few exceptions, I’d prefer if DEVONthink functions currently using Control as a prefix for shortcuts didn’t have any shortcut at all (when no other logical choice is available) and instead let users add ones they’d like. As an example, I’ll never use Control-Command-T for Format > Style > Styles… so I’d rather it be available for something else (possibly, but not necessarily, DEVONthink-related).
I still hope Apple eventually decides to significantly improve shortcut management:
If Apple wants to provide a useful, standard, system-wide human interface for user-customizable keyboard shortcuts — and I think they should — they need to provide a system-wide mechanism for applications to register all of their menu key shortcuts. It would mean that this hypothetical new menu key customization feature would only be available for applications which explicitly support it, but there’s simply no other way it can be done well.