Wong Shun-leung said that when you punch the head the brain hits the side of the skull. If the brain is against the side of the skull and a second hi… - Wong Shun Leung

..... when you punch the head the brain hits the side of the skull.

I think the kicks in Wing Chun are enough. It´s much easier to use your hands than to use your feet. Your hand is able to reach your opponent long before your foot. Why take the long way to attack (circle), when there is a much more direct method of attack? If you are using your hands, then your opponent can´t see a kick coming if you have to use it. When you teach Kung Fu, you can fool a lot of people, but not yourself. You can make like a movie and do many complicated movements and kicks, but you only fool yourself as to whether that would work in a real situation of life and death.

For low side kick attacks, Wong Shun-leung uses the feet. For knee attacks, he said if you hit straight the knee cannot really get you. Against the Thai boxing round kick Wong kicks straight forward, rather than use a clashing force with a Bong leg. This forces the kicker straight back.

In Wing Chun if you throw two fast punches to someone's head they'll be knocked out. The first punch causes the brain to go to one side of the skull. If a quick second hit comes, the person is knocked out. If you withdraw the hand to give the second punch, then the brain can recover (will have more time to recover), but if you don't give this time then a knockout results.