The Nazis started use of Zyklon B because the concentration camp guards felt that mass murder using heavy machine guns with the victims standing on the precipice of a mass grave was too “crunchy.”
True fact, except the Nazis didn’t use the word “crunchy,” irony not being a prominent part of the German concept of humor.
Word is, Himmler upchucked witnessing an executing and decided that gassing would be more humane.......for the Germans.