I was taking that same course from Master Jun Wui Sui, but he never explained how you got your opponent the keep standing there while you kicked him in the balls repeatedly. Everyone of my opponents kept running away after my first attempt, or decked me with a round house punch. When I finally cornered Master Jun, he admitted he had the same problem with the "Whirlwind of Never Ending Pain" kick and told me that what one must learn from practicing this discipline is that the Never Ending Pain is one's own!
LOLOLOLOL