One uses metaphorical language to describe wine because our language is under-equipped with literal terms to describe taste and smell. Whatever scent molecules produce the smell of violets surely have a technical name, but it would be vastly less informative to employ it in describing the nose of a glass of wine. Metaphor, in winespeak, is a form of shorthand.
Unfortunately, in most other genres, metaphor is a form of indulgence. (C.f. any Tom Friedman column.) It's why reading reams of tasting notes is so tiring. To process metaphor-heavy winespeak in the first place requires a mental adjustment, even for someone who employs such language often. And the impact is diluted the more one reads it. I sometimes fancy that in a perfect world, writers would be penalized for applying such descriptions as, 'An explosion of glimmering blueberry fruit laced with woodsmoke and bacon' to anything found at, say, Tesco's.
In such a world, where hyperbole were reserved for special occasions, it would be a lot simpler to do descriptive justice to rightly famous mouth-watering appellations like Chambolle-Musigny, and in particular - simply because they're the ones I've tasted most recently - the wines of Domaine François Bertheau, which estate was the last stop of our whirlwind Burgundy road trip last fall.


