Re: The obverse also applies in some cases
It was actually in a computer science lesson that I was in back in... must have been about 1981/2... I remember we had one Commodore PET for the previous year and had just received one BBC Micro... anyway, the teacher handed out a mock assessment paper under exam conditions and instructed the class that when they started the clock the students were to turn the test paper over and follow the instructions at the top very precisely.
The instructions said "Read all the questions carefully BEFORE beginning to answer question 1".
Question 1 was "What is your name? Write your answer on line one of the coding sheet provided, putting one character in each square."
Question 2 was something about a BASIC command, then there were some more obvious questions... at the end of the list there was some more advanced but also obvious stuff... and just before the 2/3 of the way mark down the page there was a question that said "Having read this far, answer question 1 only! DO NOT attempt to answer any of the other questions. Raise your hand when you have answered question 1."
The various questions just above the one telling you to stop and answer question 1 only had strange instructions like "Draw a picture of a chicken", "Take one shoe off" and "Make a noise like a duck".
Needless to say there were two people, including myself, who sat there with their hands up for about 30 minutes whilst the rest of the class were making duck noises and taking shoes off and drawing pictures of chickens etc etc.
Learnt a valuable lesson that day. I wonder who else could have been in that class...