"Dr Drang" is a pseudonym. He doesn't use his real name to blog, and goes to some effort to obscure it (for professional reasons).

Edit: I was wondering why Dr Drang, and found the answer here[0]

> When I started blogging, I thought I’d do more political posts, and it seemed like a good idea to keep my online and real life personas separated. I didn’t want potential clients Googling my real name and having all the hits come from my personal blog.

> I do have a Ph.D. in engineering, with an emphasis in stress and structural analysis.

> “Drang” is the German word for stress and is part of the name of a famous engineering textbook, Drang und Zwang, written by the father and son team of August and Ludwig Föppl. The father, August, also wrote an even more famous textbook, Vorlesungen über technische Mechanik, but “Dr. Vorlesungen” just didn’t have the right ring to it.

[0]: https://512pixels.net/2012/06/writers-i-read-dr-drang/

You are drawing all sorts of mean and nasty conclusions about someone's character (and feel so confident about them that you went ahead and voiced them to the world) based on few if any data points. Surely you wouldn't want other people to jump to conclusions about you based on an equally small data set (for example, the fact that your account is named after something that's the college freshman equivalent of sniffing glue).

Thanks for the detailed psychological profile of the Dr.

Why wouldn't he use the "Dr." preffix if he's a doctor?

It's a bit in vogue these days for PhD non-MD to forgo the title in informal settings. Refusing to do so can appear egotistical.

Whilst this veers off-topic, I don't use the formal title, even though I have earned the right to do so. It's actually not just a matter if humility. I find that, when introduced with the title, people ask me for medical advice.

I am a mathematician, not a physician.

I think the opposite. It's unfair for medics without a PhD to be called doctor. If you have a PhD you've earned all the rights to be called doctor and to use the preffix whenever you feel like. I would if I had a PhD.