A few years ago, there was a survey done on patients' attitude toward doctors. The original thesis was that calling yourself Bob, throwing off your white coat, and bouncing into the examining room in jeans and sweatshirt would help with patient relationships - you know, the doctor was not intimidating, or (horrors) formal.
Instead, they found that most patients *wanted* the white coat. They *wanted* Dr. Smith, rather than Bob, because they needed a doctor. And they wanted one who gave off an air of "competent professional". Dr. Smith, they felt subconciously, has a better chance of helping them than Bob.
I'm sure Bob is a nice guy, probably a good doctor, who believes that avoiding calling himself Dr. Smith is helpful to his patients. However, he may be turning a lot of his patients off, or at least not using social cues to establish their trust in him. Part of healing is psychological, and he's not using it to his advantage.