Doctors hate boxing because they have to pick-up the pieces when someone damages themselves, and if you step back from it a bit, deliberately putting yourself in a position to get hurt does sound stupid to someone who has not stepped in the ring and doesnt know how a fight makes you feel. Breasts tend not to be a major target because more imediate damage that can weaken your opponant can be done by targeting other areas of the body and anyone with good hand positioning doesnt leave their chest that open anyway. Psychologically most females identify their breasts with their femininity so attacking their breasts is a way of making them identify as female not a fighter even if only briefly and is a show of dominance. Pain for the sake of pain is similar, when someone inflicts pain for the sake of it, it is a show of control and dominance basicly its off putting to have someone look you in the eye and systematically hurt you without it serving a fight ending purpose. It works on the mental state of the opponant by suggesting that they are no real opponant and can be toyed with until you are ready to take them out. I have never been kicked or hit in the chest so I dont know if it would hurt any more than anywhere else, but Im pretty sure its going to hurt like hell at some point. And quite franky I fight because I love it not to provide some perve factor to an audience, I dont care how much body the audience wants to see they can watch the ring girls if thats what they want or go to the mud wrestleing. I would rather people appreciated my fighting than saw me as nothing but some tits in the ring and credit for the spank bank. Everyone wants to be seen as attractive but its not something I focus on when Im preparing to fight, if something made me look ugly in the ring but helped me fight I would use it, regardless of audience esthetics.