I have some thoughts about the structure of the book, in how the examination of the Dialogues of the Courtesans is placed apart from the main presentation, as if it were a different type of evidence. As the most complex and extensive presentation of sex between women in the classical era, I can see how it makes sense to sort out the simpler texts first and then use that analysis to interpret the dialogues. And given that it's an adaptation of an independent article, Boehringer may have had structural reasons for separating it from the overall outline.