Currently if you protect a file that is already protected, it will increase a count attribute, so that you can see how many times it was protected by a given user.
However, there is no-way to decrease that count.
If you unprotect a logical file, it will remove the protection completely.
Afaics, there is nowhere that is relying on the count, and the current semantics aren't helpful.
(the original intention may have been to act. as a sort of link count, but if so the semantics were broken long ago).
I think we should remove the count and make it effectively what it is in practice a boolean toggle (but still per user).