To add to this, I used to be very critical of doctors but having had various metabolic challenges and going off and learning all that stuff, medicine is a difficult confusing mess.

If you disagree, read this (about 2/3 of which is relevant to me):

http://www.amazon.com/Endocrinology-Adult-Pediatric-2--Set/d...

There are thousands of diseases and not that many different symptoms. Most serious diseases have numbers of mild conditions that look very similar.

This is not to say there are not major issues with the way medicine is researched and practised. And that being a doctor does tend to encourage people to be arrogant and overconfident. And that the medical basically selects people who are good at memorizing stuff.