I just read it and thought some of it was bad advice. Not too surprising, since it's advice about how not to fail from someone whose worst failure was, apparently, taking too many classes and thus taking an extra year! horrors!

Funny thing is that rather late in my graduate school career, what I noticed is that the people I admired and who were doing well (faculty and students) allowed and encouraged their curiosity. After the talk, they'd stay and discuss the result until they understood it, whether it was their area or not. They'd attend classes if (and only if) they wanted to learn stuff.