By "keep your course load light", I think that he wasn't saying "do only easy courses", rather don't overload on ones which can seem objectively hard, say, the honours variant of every course you're taking and taking 6 courses per semester instead of the usual and minimum 4. (for example)
He wrote
another article on people with accomplishments that one finds insane and impossible to achieve. The basic idea is that if one were to think hard enough about the said acts and break them down, it all makes sense and looks somehow doable. He also uses himself as an example - he got into grad school for CS.
His thoughts/observations are also usually very general and as such, if one likes what he says, they'd have to be willing to twist it a little to adapt it to their life. Another thing, as Lavabug pointed out, some people thrive under stress. And for some people, doing a double major and getting involved in 2 different research projects is bliss.
I'm more laid back and my previous approach to studies made me way too stressed for me to seriously complete, let alone understand, anything. Now, my approach is a more casual one. Whether it's for studying some music theory to later then apply it to guitar or if it's studying physics. I know what I have to do and I just start doing it without thinking too much about deadlines. When I'm bored, I switch to something else. It seems to be working so far.
Also, Choppy, the spontaneity thing has a lot to do with individual personality traits. With more time available, one might be able to just walk across campus and try get involved in a rather casual activity. Maybe it's a poetry reading or perhaps it's taking that new girl you just met out for coffee. It could also just be sitting under a tree with a book. If one is perfectly happy staying in a surfing or watching TV, there's no problem at all. If one isn't happy about that, then more free time (i.e, when all required work for the day is completed) is available for one to do more "spontaneous" things. I used to really make things hard for myself when I wasn't able to finish my work and eventually, I'd neither get the work done, nor would I do something I enjoy and would just stay in, doing something on the internet. The key is to set more short term goals. Say, I have my calculus tutorial on Friday. I'll do my required reading on Monday and Tuesday, while doing a few problems. On Wednesday and Thursday, I'll finish the problem set. That way, I'll be doing a bit of every course I have, without feeling overwhelmed and still getting everything done.