Just saw this thread. I don't think "beaters" should get off so easily.
I don't care which direction the beating comes from or whether the beater is male or female. If you abuse another person in order to make your self feel whole and make the other person feel less human, then you deserve to be impaled and more. Much more. I don't have any problems with consensual, bipolar abuses, but one dominating the other through fear is not write, no matter how you play it up.