Haha did that today for maybe the 2nd time ever.. tried to go handless to adjust my bag and attempted to stand up and coast in the process. Yeah, didn't work. I didn't fall but came close. I did the huge bounce move, nearly flew off the bike, caught myself by grabbing the bars again with one hand which then naturally pushed the bar forward, causing a dramatic swerve which I countered and then swerved the other way (again, with dramaticicityness) before I got my other hand on the bars and straightened out.

I'm sure it was all quite impressive from the sidewalk. Probably looked like some advanced maneuver to avoid potholes.... or just like a complete berk losing total control of the bike for a few seconds.