true but they do fall for it most of the time.
I have only ever had 1 FO who after reading the rest off from memory when given the 7800 just said "bog off you piss taking porridge wog"
I really enjoyed flying with him for two weeks. It stimulated me into thinking theory and basic principles again.
Andy go and search for transponder theory. Honest If I just tell you straight you will have forgotten it within a week. If you go and look it up you will think "piss taking porridge wog" and remember it for life.