You are still meeting force with force. I don't think that's a god idea for a young woman to do to a 220lb man,do you? If you are similar in size maybe,but you are still leveling the playing field instead of taking advantage.
IMO the block then punch scenarios are bad applications for the breakdown of any forms. Parrying and avoiding are much better suited for addressing punches and give you the advantage. If someone throws a punch and you block it forcefully what stops him from punching with the other hand? You would just be standing there blocking over and over.
Double shuto (knifehand block) - This move usually comes back first then both knifehands are thrust forward. One application for this is an attacker punches you follow the punch back while stepping forward and strike it toward you with the knife hands (two hands/arms against one) just up from the wrist and the middle forearm (that's the back motion) Then the double knifehands strike forward on the neck and or middle bicep. Attacker will be incapacitated from the blows. Trust me this is an effective appication for this 'block'.