They work because they capitalize on the mistake that the oder boxer is doing. Not staying on the back leg and he is not taking his head with the step. And if he is going backwards while loading on the back leg he is going to shoot the most powerful right that he can throw while you are going forwards... Its a recepy for desaster. The idea of punching infront of you is good. It explaynes the problem that comes from punching the heavy bag... The boxers are used to punch the fat bag. No one has head like this.