Following a lecture I had just given, an undergraduate student approached me and asked if I had taught a girl called Sara some years before. I replied that I had. I remembered her very well. "I thought so," the student said. "She tells the same stories that you do."
Before coming to university, this student had attended a preparatory course elsewhere; Sara had been one of her lecturers. The anecdotes she was now using to illustrate her teaching were ones I had used for mine. I did not mind that my stories were being (re-)told by somebody else. Instead, I was delighted. Something about my teaching was proving useful!
There are plenty of textbooks to consult for the facts and figures one needs to teach a course. However, they do not contain anecdotes. Those I had told had stuck in Sara's mind. Anecdotes provide embellishments not found elsewhere. They serve as aides-memoirs. They never appear in isolation. They are always used to illustrate course content. They are hooks upon which the much drier facts and figures hang and come to life. They serve to make what is dull more vivid.
(I think, that makes this anecdote an anecdote about anecdotes.)
