The five conditions make sense and put slapstick into a better perspective for me. I haven't been so keen on most slapstick. I don't mind the physical comedy, the pratfalls, banana peels, risk-taking, etc. because the action is limited to one person. I haven't like the head bonks, eye pokes or face slaps - too personal and invasive. I love Buster Keaton the most, and Charlie Chaplin, but not so much the Three Stooges (except for Swingin' the Alphabet, which is clever and not physical).
Agree, and am thinking that historical context matters so much. This prank seemed so innocent, a light-hearted view that would lead to good-hearted laughter. "Revenge" was achieved, but no one got hurt. It would be interesting to trace the evolution of slapstick from this to more malevolent pranks and pranksters in films of recent decades.