I had the same issue recently, but for several real folders. (So that users could login, have read access to a communal "Public" folder, and then individual access to private folders.)
I assumed the Virtual Filesystem setting wouldn't apply as I was working with real folders, so I ignored it. I created a real-folder subfolder for each user, renamed them in HFS to the md5sum of the user's username, hid all of them, locked them down to the appropriate user, and just added a simple Javascript MD5 function where the user who wants to visit their private folder simply enters their username and clicks a "Private Folders" button. That brings them to example/HugeMD5HashOfTheirUsername or, if they enter someone else's username, it simply denies access and gives a 404.
It only took a few minutes to set up, and it solved all my problems.
