Random Literary Conceits

I'm currently reading The Bride Stripped Bare by Nikki Gemmell at the recommendation of my wife. Its not typically the kind of book that I'd pick up on my own, I'm more of a non-fiction kind of person, but its turning out to be fairly interesting. Of particular note is the fact that its written in second person. I don't believe I've ever read fiction in that voice before. Initially it was a little jarring, especially considering that the putative protagonist is female, but I got used to it fairly quickly. I suspect that a female reader might find it more immersive because its easier to identify with the "you" of the story. In the very least its an interesting experiment with generally positive results. The blurbs on the jacket call it an "erotically charged tale of tragic yearning", and up to a point it actually manages to deliver on that promise. There's definitely a charge, its erotic, and there's some tragic (possibly melodramatic) yearning going on. But then it goes downhill... chapters (or "lessons" as the book calls them) 72-74 are little more than really bad porn. I mean, its hardly better than the crap you can pull off of USENET... we're talking Clan of the Cave Bear bad here. Nikki, why'd you have to go and do that? You had a pretty good book, but then you fucked it up with mediocre love scenes. Here's another thought, though, which is only tangentially related. The story is presented as a "found manuscript"... a father presenting the writings of his mysteriously disappeared daughter to a publisher. I'm not done with the book yet, so maybe that makes more sense later, but right now that presentation doesn't seem to be adding anything to the story. This came to mind because the book I read prior to this one, The Geographers Library, also presented its story as a manuscript. In that case it wasn't "found" but rather was presented as the protagonists memoir of events written down for the edification of another character. Again, this presentation was little more than a couple of pages bracketing the main story that really didn't seem to add anything to the book as a whole. Now there's a literary tradition of presenting stories as manuscripts of various kinds; one which springs to mind readily is Kirkegaard's Either/Or. In that case, however, the presentation was integral to the book as a whole and consisted of far more than a couple of pages at the beginning and end. So what are these modern authors trying to achieve by presenting their stories as manuscripts, since the presentation really doesn't affect the interpretation of the story one way or another? I've a couple of theories, but their fairly cynical and I can't support them based solely on the two instances mentioned above, so I'll just leave the question hanging as is.