The majority of Overheards in D.C. fall into only a few categories: funny sex stuff, dumb tourists and weird kids. There’s the occasional amusing political thing, or some quip that somebody sent in because they think they or their friends are funny. But there are always those that make absolutely no sense unless you are knowledgeable about some extremely narrow area of trivia, such as say, documentaries about lost and possibly mythical Brazilian cities. Quote…