Diane Wilson wrote several books, including
Holy Roller http://www.amazon.com/dp/1933392827/?tag=absolutewritedm-20
and
An Unreasonable Woman (which is also listed on that page--and btw, I got that lovely simile in the OP, the one about dogs and water, from the intro to this one)
What really made these books was the language used by Ms. Wilson--it was beautifully evocative and absolutely littered with simile and metaphor. But in reading them, I noticed that her similes and metaphors were always related to the text; in Holy Roller, things were compared to things from biblical stories or related to the culture of the church, in An Unreasonable Woman, they were always somehow related to the sea, or to shrimping, or to something that was near-and-dear to us South Texans. Every simile and metaphor was evocative not just because the comparison was apt, but also because it brought us deeper into the mindset of the MC (who was also the narrator.)
She even brought up the sea in a character description (and how's this for squeezing in the similes and metaphors): "Baby's [a male character's nickname] smell was as hard as the walls in the house, and around his shirt collar and his hair was a scent of the sea, and against his wrist was a layer as thick as my hand."
So, I'm asking: how important is it, how desirable, that our similes and metaphors relate to the themes of the text?
My inclination, after reading the two novels above, is to say that it's very desirable, that it really helps the reader to get a feel for what's going on...but Douglas Adams and Terry Pratchett often use them just to give a sense of the absurd, and that seems to work well, too.
