Moving "Special Folders" and the USERPROFILE variable

On a laptop running Windows 10 Home I tried moving the special folder "Videos" to another location, by clicking on the folder's Location tab in Properties, and using the Move button. It appeared to work fine, but I noticed one odd thing: Before the relocation, if I typed the following at a command prompt:

cd %USERPROFILE%\Videos

Explorer would open to the Videos folder. If I run the same command now, it tells me "the system cannot find the path specified." Of course this is because %USERPROFILE% still points to its original location under C:\Users\[username].

1. Is this behavior involving the environment variable normal?

2. If so, how do programs know where to store videos if Windows can't find %USERPROFILE%\Videos?

Background: I'm trying to figure this out because I'm trying to diagnose a problem on a desktop machine which I just upgraded from Win 7 Pro to Win 10 Pro. I am seeing duplicate special folders under my username. I assume this has something to do with the fact that in the past I had relocated them to a different drive. I know I could try to get rid of the duplicates by restoring them to their default location and then moving them again, but first I want to understand what's going on with the environment variables.

Thanks!

FOLLOW-UP: I see that the values stored in:

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\User Shell Folders

indicate the new locations of special folders after I move them. Is this the (only?) way Windows knows, for example, where "My Video" is located? How would one get to it from a command line?

What's weird is that on my desktop machine I have two "Documents" folders under my username, each of which has a Location tab, even though only the "moved" folder is listed here in the registry. Why does windows think the folder in its original location is a "special folder?"

General question: Once you move a special folder to a new location (using the Move button) shouldn't the folder no longer exist at it's original location? Or does Windows keep around a hidden copy for some compatibility reason?

Thanks. I think I've resolved it. I switched all the special folders back to their default locations, and then switched them back to the location where I want them on another drive. (I temporarily emptied them all first so the moves would be instantaneous.) Now I see only one of each kind of special folder.

And the CLSID Key (GUID) shortcuts all seem to work: if I create a new shortcut using each of those keys, it opens the correct folder. So I think I'm good to go.