The variation in people absolutely amazes me. I'm only able to arrive at an intelligible conception of how the author has pulled this off by concluding that his lifestyle expectations, workflow assumptions and cognitive habits are vastly different from my own. As someone who struggles with deep practical motivational problems working on things in which I am theoretically, conceptually very interested (call it burn-out on coding if you like) and sometimes go days or even weeks without moving the kind of mountains that the author consistently moves in an hour or two every day of his life, I am awed.<p>Of course, sometimes there's something you don't know. I don't mean to impugn the author's credibility or authenticity in any way (how would I know?), but some of the people I have encountered who claim Herculean feats like this turn out to have mixed up the variables differently than they say, even if their omissions are unconscious. That is, I've seen people who, in the author's shoes, are 1) getting a PhD in something fluffy and not particularly rigourous, or perhaps in an institution that fits that description, 2) have grandparents who take care of the kids most of the time, 3) are doing startup work that is also not overly intensive, or move at a glacial pace. Even then, it would still be an impressive accomplishment to consistently pull through on #1 and #2 whilst complicated slightly by #2 without losing motivation, interest or focus!