One place, with 60000 employees, had an 'editing cone' which was an actual traffic cone that you had to have in your cube if you were writing to the Access file on the SMB drive
I LOVE this image. Acquiring a physical lock on the file. Think of the manager who thought of this beautiful idea, probably not a programmer by training. Awesome.
And yes, since it relies on human conformance, it's bound to fail on occasion. You can say the same thing about any piece of software you ever came across or wrote.