I wouldn't say it makes bisexuality meaningless. Technical definition of 'bisexual' means having sexual responses towards both genders and could end up settling down with either. You can be homosexual without being bi, or at least consider yourself to be, but you can't really be bi without being homosexual, because homosexuality just means having sexual feelings towards your own gender. When you stop making it a word and start making it a lifestyle and a pigeonhole is where it gets dangerous, and I can see why Hughes might not want to define himself by those terms, but if that's the case, then it's his responsibility to outline in clear terms what 'gay' means to him. He chose not to, then made his admission. I'm not saying you're wrong, but I am saying that he handled it extremely badly. It's a pity, too, because standing up and making that admission took guts, and that's the kind of thing a party leader needs.