I never managed to impress my Professor but I did leave a good impression with his wife
I was at university between 1975 and 1978 where I studied Electrical Engineering. Being an old fashioned type my Professor used to invite three or four students to tea every Saturday afternoon and one weekend it was my turn. So, I turned up in my suit and sat there with the other students drinking tea and eating sponge cake but eventually the tea began to have an effect and I needed the toilet. So, I asked the lady of the house and she directed me upstairs.
Stood there in the 'smallest room' I could not help noticing that there were two rolls of toilet paper, one soft roll and one roll of the hard stuff like tracing paper that they used to use in public toilets. This matter slipped to the back of my mind but it kept on resurfacing until I just had to ask. So, waiting for a quiet moment, I asked the Professor's wife about the two rolls.
"Oh", she said, "that's for Frank, the roll of soft paper is for normal use and the other roll is for when he's sitting on the throne and needs to write down a good idea before he forgets". It turns out that I was the only one of his students brave enough to ask.