Agree 100%. The corollary is that, if you must play, make sure that you yourself are the best expert of your medical history, symptomology, and candidate hypotheses about what may be going on with your health. This is difficult, and perhaps futile, but the sad truth is that due to time issues (and probably information overload) it's your job to a) bootstrap the MD with whatever is relevant about your condition, and b) sanity-check the MD's decisions.

Failure to do either of those things is likely to result in either suboptimal care in the best case, actively misleading care in the worst. I guess the silver lining is that Google + intelligent and motivated person >= most MD diagnoses in my experience.