I don’t remember that trick, but IIRC, “LOGO” was short for “LOGOUT”, right? :) When we started using PCs, we’d use the NET SEND command to spoof messages to a list of people. It would put your computer name at the end of the message, but it just looked like you were the last username in the list!
We used to log people off of their IBM mainframe terminals by doing that (early 1980’s). They had to wait 15 minutes for their session to time out before they could log back in! :D
I’m surprised no one told me to “Take off, eh?” :D