I think it depends somewhat on who the 'audience' is. Some monographs (John Sexton's for instance) include at least one or two photographs with explanations of the techniques used to make them. In fact, Rolf Horn has a rather extensive explanation of his techniques (some of which completely surprised me, like extensive print retouching... as much as 2 to 3 hours per print) on his website as do others. Clearly, they assume that a fair number of viewers are also photographers who are both curious and interested. Maybe, by doing so, one may be spared the 'did you do that in Photoshop?' query.
I think being open and personable about your work is a good thing. As Brian stated it's even good business to tell a 'story', if there is one, at an opening. But beyond that, if there's 'magic'.....just smile and let your eyes twinkle!
I like how Ansel Adams approaches it in Examples, with ample explanation for how the technique allowed him to render the scene differently than it appeared.
Photography would be pretty easy if what we saw in the world would inevitably end up in print. But it takes an effort to make great images, and that's true irrespective of medium. I'd think it would only illustrate or highlight one's skill to talk about the original scene and what kind of effort it took to create such an effective image.