I used to work at a place where we were required to give a 20 minute talk every 3 months or so. The reason the talks were 20 minutes was from the old Calvin & Hobbs cartoon where Calvin remarks “Anything you can’t explain in 20 minutes isn’t worth knowing.”
This seems to be true for some values of explain.
I was once a guest at a Rotary club and their scheduled speaker, a fire chief, failed to show. My dear wife volunteered my services so I gave an unprepared talk on the various kinds of “electric paper” that people were playing with at the time. I had fun and people asked relevant questions and told me after that they understood and enjoyed the talk. They invited me back a couple of months later to do a prepared talk about quantum cryptography.
I, for one, agree with Calvin, (since I have two cats named Calvin and Hobbes.) I also get an email comic strip each day of C&H, and have several of the albums of the strip.
It’s good that people know enough (or are curious enough) to ask the right questions. I have an insatiable curiosity, and anyone close to me will be beset with queries about whatever I don’t understand.
Some folks are not too patient... ;o]
I am generally prepared to discourse at length on almost any subject.
Normally I would have to be physically dragged from the lecturn to silence me, a function my wife is only too happy to provide.
I worked for a short time at a place where material was introduced in training sessions by a rotating list of conscripted volunteers.
I think they still talk about my presentation.
“Anything you can’t explain in 20 minutes isn’t worth knowing.”
I need a copy of this to send to my preacher.