> recently, both John Adams and Carrol Cox said that a good rule of
> thumb is never to trash an author/artist.
Not quite.
As a critic, I think the only works of art worth a bad review are works which have an outsized and unreasonable positive vibe going. Here's a real harsh trashing that was well-deserved, which I found while googling (what else?) sexist asshat: http://www4.ncsu.edu/~tenshi/Killer_000.htm
I trust my critical abilities more greatly when I'm favoring something. It's just too damned easy to snark--response to something good, on the other hand, is rare, and often takes a lot out of you. That's worth writing about.