Although he was telegraphing pretty bad, that is a back roundhouse into a back roundhouse. I had never seen that done before in my time time doing TKD
I had done many a double back roundhouse. But mine would be a gimp, badly timed first one as je-bait. Then when they rush in confidently towards my exposed back, I’d whip into another much faster one to their face (same leg though). Other kids would fall for it every time
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