The public restroom wall aspect aside, it seems like it would be really tricky to draw any kind of recognizable "picture" at jet speed, and get the proportions right. At least with sky writing, each letter is a fairly tight maneuver, while this extends (if you will) over some miles. I'd say there was some tricky piloting involved, along with the juvenile sense of humor. Any pilots who can tell us what difficulty level of flying this is?