I just walked back from giving a short lecture across campus. It was a 20 minute performance, complete with (a) slides that articulated and illustrated common issues that students struggle with in writing a technical report and (b) enthusiasm.
As I walked back, I added up the time spent looking again at the batch of reports and my summary comments; making 14 slides, with examples from student writing; and mentally rehearsing. Time? Seven hours.
Sometimes I’ve heard professors tell students it takes an hour of preparation for every one minute of presentation. I did not spend 20 hours on my talk today, although perhaps all the time spent reading & commenting on the papers that led to this talk counts for preparation.
This makes me realize, though, that some professions (all?) are like icebergs: most of what one does (as a teacher, writer, dancer, bass player) is hidden from the people we work for (students, readers, fans, audience).
Post script: Later Jimmy asked, “How many people were in that lecture?” I answered, “Fifteen students and one professor.” And he reminded me to include those numbers in my ratio, which in turn reminded me that it’s not all about me and my experience!