That weird stumble you make when you are walking with flip flops and the toe part of the footwear bends into the sole,because of how your feet were too close to the ground. Hence, the term is used.
Friend1: Dude are you okay, are you having a seizure?!
Friend2: Calm down damn it, I almost had a Flip-FlopShuffle when we were walking down this bumpy-ass sidewalk.
when you shit your pants and have no time to go to the bathroom, while walking you drop your pants half way and flop the turd out without breaking stride.
Hung Lu was late to school and shit his pants so he did a quick dropflop to make it to class on time.