"If you really want a shot at getting close to this woman, you have to wait until there is a crack in the lack of respect her boyfriend has for her. Watch for when he is late, or disrespectful, or inconsiderate. Casually mention that you would never treat a woman like that. Reinforce how she deserves so much better. Store the details. Then wait for him to mess up big."
-- From Staceyann Chin's column in The Guardian, Why Chasing Straight Women Still Thrills Me. Chin (rightfully) took some heat for her essay on how a lesbian can bag a straight woman - complete with underhanded and manipulative tips like this one.