So recently I have been testing out the jumping round kick off the back leg during sparring, and here is what I have learned so far: advantages: 1.the height during the kick changes the angle of attack, forcing the opponent to change their guard to defend against the new angle of attack 2. the turn in the air allows the kick to come off the back leg at a distance that would normally be too close without moving back or switching your feet somehow, also opening up new angles. 3. makes for a good surprise attack because of 1. and 2. 4. it looks pretty disadvantages: 1. it takes an incredible amount of timing and predicting what your opponent is going to do in order to pull it off. 2. easily telegraphed early in the kick 3. slow 4. practically useless as an initial offensive technique, since 2. and 3.. 5. expends much energy 6. limits targets to those higher up (upper torso, head) Something that surprised me is that when sparring, nobody rammed me out of the air. When throwing the kick I was doing my best to disguise it and time it for when my opponent is not in a position to move, so perhaps even though I didn't do this well enough to hit every time, I did it well enough that they couldn't easily counter. I did manage to land it once, against a red belt. And I managed to throw it against a 3rd degree without receiving a counter, which I did get from him to just about everything else I threw. Something that probably did not make it any easier to land is that I did not throw any other type of jumping kick, thus making it very easy to identify by the jump. I plan to add other jumping kicks as I become proficient enough at them to use in sparring. I think in view of training, it forces you to improve your timing, your ability to predict your opponent, and your ability to mislead your opponent. As far as self defence, I think the likelihood that an opportunity to throw this kick would present itself is dim, and that it would be the best technique for the situation even dimmer.