If your block hurts you as much as the other guy, you're doing it wrong.the problem with that is that forces being equal and opposite what ever force you instill into your oppoinent with your block is also felt by you. Now this can work if your hitting bone in to muscle as he get more damage for the force created, but bone on bone or flesh on flesh and you are doing exactly the same to yourself as you are to him.. I my instructor keeps wacking me with a full force block and it hurts, but I know it hurts him just as much
I dont see deflective blocking as defensive, more it opens him up to a counter attack, but I find blocking,difficult as I would rather move than block if I can