Here's an interesting look at crime fiction. The question here is do we want passion in our procedural? And yes, I know they started out talking about noir but it got lost in the essay. For me, I enjoy a little bit of romance but when the romance/relationship/sex overshadows the crime story then I'm gone. It's one of the reasons I stopped reading Sanford's prey books. They became more about his home life than the crime. I do believe that there needs to be a good balance of both to make a good book, no matter the genre. Truth is that passion in one form or another is what makes the world go round and keeps the reading interesting.
Hat tip to @tommysalami!