I disagree with your analysis of the diner scene. I don't know that Tiffany's admission of casual sexual activity is to be viewed as a mechanism to attract men to pay attention, or inviting the viewer to fantasize about her. I liked the scene because they both are trapped in mental illness. There is nothing else in this scene, to me, except Pat learning more about Tiffany and responding to it in a way that, under the same circumstances, most people would find uncomfortable and disturbing. For instance, if a woman who is portrayed in the film as a perky, fun character had made these same admissions as Tiffany but with a different tone, she may be considered a carefree, happy-go-lucky free spirit. But if Pat across the table had asked the same questions, he definitely would have been labeled a creep. Conversely, if Pat had been painted as a man without any mental affliction, this same scene would take on a very derogatory tone, as he would try to change the subject and Tiffany would fall to the wayside in his affections as a girl to be pitied. This scene gives Tiffany depth. It gives their relationship with each other depth. I thought it was masterfully done.