Yes, we can read the "local file" location from the Revit.ini file, but it would be cleaner if we could get and set it (and ALL the properties in that file, actually) through simple API calls. Providing official methods would be better than everyone rolling their own Revit.ini access methods.
Our reason for wanting it: we create version-specific subfolders ("Revit 2019 User Files", etc.) and want to verify that they're configured for each user.
See also Current location of local revit documents?