I didn't read the whole thing - it's not concise, that's for sure - but the general advice seems to be: Go find a lab job and see if you like it. Though his examples are specific to biology, I can't figure out what part of that advice is specific to biology. I did it in experimental physics and it worked out just fine.
Sure, the article is about about pursuing science rather than thinking about it. But that's the author's whole point. Enjoying a career is all about enjoying the day-to-day work: If you love thinking about DNA but don't love pipets, you're going to be unhappy a lot of the time, because life in the lab is about 10% deep thought and 90% pipets. (Or, in the semiconductor laser lab: 10% deep thought, 50% misaligned optics, and 40% mysterious process problems that you will never entirely understand, but which you will eventually solve by spending months on end turning knobs in a strategic manner.)
Same general advice applies in engineering: do your best to attach yourself to a lab, and see if it catches your fancy. Best way to test-drive a career choice.
He's kind of down on textbook-and-problem-set coursework and large lecture classes. This is not universal. Some large lectures are large for a reason -- the professor is a star. And some textbooks are really good, and some problem sets are worth sweating over.
Sure, the article is about about pursuing science rather than thinking about it. But that's the author's whole point. Enjoying a career is all about enjoying the day-to-day work: If you love thinking about DNA but don't love pipets, you're going to be unhappy a lot of the time, because life in the lab is about 10% deep thought and 90% pipets. (Or, in the semiconductor laser lab: 10% deep thought, 50% misaligned optics, and 40% mysterious process problems that you will never entirely understand, but which you will eventually solve by spending months on end turning knobs in a strategic manner.)