there is no way around having some kind of DB which potentially becomes big and outdated
But there are ways to facilitate clean-up. Timestamp the database records of each folder. Whenever a PMS list for a folder is created or amended (and perhaps accessed) record the date/time. Then users can purge PMS lists older than a certain time. By "accessed" I mean the user viewing that folder in XYplorer with PMS mode on. Then the purging can be applied to folders whose sort order has not only not changed in a long while but also the user has not viewed that sort order in some time.
If the "accessed" time is not recorded, files added to the folder but not yet manually sorted (i.e. those that get appended to the end of the list whenever that folder is viewed with PMS on) would not trigger a timestamp change.
Being able to generate a list or search result of all folders with a PMS would also be useful for other purposes.
P.S. PMS is possible not the best acronym to use for marketing purposes in English (Pre-Menstrual Tension)
Not sure what I think about desktop mode/mindmapping for individual folders
The term "mindmapping" is a bit pretentious, but it has become established. "Mind-mapping" software hasn't really caught on, perhaps because it's one more set of concepts and controls for people to learn. Desktop Mode, Desktop Folder and Portable Desktop are terms people can immediately understand. It is not really a "new" idea. It is just porting the idea of real world noticeboards (the kind people use to organize their thoughts, not necessarily post information for others) into cyberspace. I don't think appeal has to be demonstrated. Just look at how most people use their Windows desktop despite its limitations.
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