Education as some kind of holy icon

An angry reader of Andrew Sullivan wrote a letter that Sullivan posted. In it the reader tries to bolster his argument on politics with his credentials:

I am a Hindu, Indian American, more educated than you (B.A, M.D., double board certified in subspeciality surgery, giving his specialty services for free for over 30% of my patients)

While I have a vague understanding that board certification is quite an achievement for a doctor, I'm not sure how this improves the political pronouncements made by such a person. I have my Masters degree, does that reflect on my general knowledge of everything? Put another way, should you trust me or my mechanic (who is a genius under the hood but, to my knowledge, not holding any kind of advanced degree) when it comes to mechanical advice.

I'm in favour of education generally. I think that everyone needs a good grounding in a variety of subjects, but at the same time we live in probably the most hyper-credentialist culture ever. "I'm a doctor, a good one, my political views are better than yours."