i remember doing something extremely similar in grade school, kids were just learning about fake punching, and how it was funny to make someone flinch, so i was in line one morning waiting for school to open, and the boy in front of me said hey check this out, and faked a punch to my face, and of course i flinched, so then it was my turn, except i didn't stop my punch at all and he ended up on the ground crying just like this guy.