Interesting. That would make his survey of rather limited value, in my opinion, because just by doing notes (including rests), durations (just from semiquaver to semibreve, including tie and dot), and accidentals, you get 18, right off the bat. Considering the ranges offered in the poll he made were 1–5, 5–10, 10–20, and 20+ (never mind the overlap if you happened to use exactly 5 or 10...), that makes it very hard for anyone who types their note input instead of hunting around slowly with the mouse to get into anything other than the top bucket. Especially since he quite explicitly said "including typical ones (like Ctrl+S, Ctrl+Z, etc.)"