Your trusted medical professionals, or in the example I cited, the people who show up to do Advanced Cardiac Life Support when you or a loved one are in a hospital trying to die. I wasn't trying to be overly dramatic it was just the first example of something I am familiar with that came to my head.

Well I suppose it's true that when they tell me stupid things, I no longer trust them--so I know my trusted medical professionals are only giving me superb advice. :)

Advice. Sure. Superb, maybe not so often as you want it. People who are unfamiliar with how medicine works, unlike yourself, jinx, and a few others, are much more trusting and do not understand that it is not an exact science, although I believe most professionals are striving to the right thing in accordance with their experience and training. I think 98% of professional still believe and try to practice the notion of "first, do no harm".