I disagree that the author considers "real world knowledge" the only kind of useful knowledge. If you read the preceding entry on "The Agony of Grad School" it clarifies that the main problem here is this person has a really high cost for context switching, plus a really low tolerance for distraction. That's a bad combination, because you end up thrashing all the time. In the preceding entry, he talks about how he wants to know what's going on in a theory of programming languages course (not really "real world knowledge" ;) but he can't due to the context switch overhead from real analysis.

It sounds like the author unfortunately hit a place that requires more classes and teaching before getting to the point where research becomes the full time 100% job. It also sounds like the author was trying to take several courses and be a teaching assistant at the same time. That's a lot of work for anyone, even people who are good at multi-tasking.

I suppose I was wrong about the author's reasoning, but I still think my description applies to many people.

Personally, I think both camps have their problems. Academic people can be quite annoying when they talk about something like they know everything about it just because they've read some paper about it. On the other hand programmers knowing only one language and framework are equally limited in their view.

I feel the author is saying that knowledge should be tested against reality. The test should not be a quiz administered in a closed classroom. Knowledge should lead to outcomes in the real world. It should be hardened against the real world.