So, for me, I read quickly and I read through books aggressively and without, as you say, savoring the experience: if it is a book with a strong character or event-based drive, I want to get at what happens to change them, or the events that drive the story, as fast as I can! But here's the thing--as you say, I do go back and read it. I'll read the same book three times, sometimes, and get more out of it each time. Once I know what the shape of the story is, I can more easily drill into it to appreciate the nuance. It's still faster than trying to read slowly to soak it all in the first time, and I think (can't prove, obviously) I get more out of it through the repetition than if I were to try to slow down and spend longer to do it only once.

YMMV, of course.