great stories! yes, i am guilty of some! and so are Instructors.
one night while heading off for a night nav, i was pax in the back
of the arrow, the instructor and student got in, fired her up, made all the calls, and off we went, or so we thought, i was surprised when the instructor gave it full power and held it there for a few seconds and wondered why we went moving! sure enough, he had forgotten to undo the rear tie down. the taxi to the run up bay was done in complete silence!