he explains more at his blog:
....... I described some of the things I’ve discovered by self-experimentation. Then I tried to say why it had been successful — why I had managed to discover such useful stuff. My conclusion is that my success came from the combination of four things: 1. Self-experimentation. Much faster, more flexible than ordinary research. 2. The Stone Age = good idea. I used the idea that our bodies were shaped to work well under Stone-Age conditions to choose what experiments to do. 3. Subject-matter knowledge. My knowledge of psychology, experimental design, and data analysis helped a lot. My weight-control theory, for example, was based on ideas from animal learning. 4. Freedom. I could do and say what I wanted. Most scientists cannot. They fear career damage. The combination of these four things is why my work was effective.
After my talk, a few people asked: Were you serious?