I’ve plowed through about a third of this, and now and again a tad of it makes sense. It’s slow going, stopping to check definitions which lead to a whole new theory that needs understanding before I can go back and get past one word.
Basically, the pleasure is still a readerly function of the text. It can still be the story, the language, the construction, the style, but as put forth by the writer and he/she is appreciated as such. But we must remember that Barthes advocates the death of the author, maintaining the the text belongs to the reader, thus making it a living thing, constantly changing and evolving with each reader, each reading.
What Barthes seeks in literature is bliss, proving the writerly function of the text. What can grab the reader(slash writer) so completely as to become orgasmic (mentally at least!) and out of the control (as we become in sexual orgasm) of the reader.
One point that was interesting (and a bit clearer than most) was this:
Is not the most erotic portion of a body where the garment gapes? In perversion (which is the realm of textual pleasure) there are no "erogenous zones" (a foolish expression, besides); it is intermittence, as psychoanalysis has so rightly stated, that is erotic: the intermittence of skin flashing between two articles of clothing (trousers and sweater), between two edges (the open-necked shirt, the glove and the sleeve); it is this flash itself which seduces, or rather, the staging of an appearance as disappearance. (p. 14)
While I don’t claim to understand it completely, I believe what Barthes is pointing out here is that little is more. The imagination can supply much more pleasurable and exciting fillers than bold display.
This, I think, is one of the best illustrations of Barthes’ writerly/readerly theory that I’ve read.