I am not an advocate of high kicks, but in sparring it always was a rush to pop a nice round house kick off the top of someones head. Once you get their attention, and they are looking for that high kick, then switch lower. Add some fast hands and the game is yours. But, I am also a believer in what you use the most is what you will use in the heat of battle. Stretching does more for you then just high kicks. It improves balance, speed, reduces injuries, and helps you to move more fluidly. I always felt that if I could reach your face, then your knee was a piece of cake. Anyways I digress, the only way to achieve the above effect is to stretch everyday. As was mentioned in early posts, never bounce, but once you are in a stretched position, and feel that you cant go any farther, that is the time to take it to a new level. If you follow this strategy, and work through the discomfort, then you will realize your goals in 3-4 months. Think muscle, but it is tendon you need to reach. Good luck.