[bryanph_]

The key question when reading any article/book/whatever is the following: "if anything, what is actually important enough to remember from this article?", or in the case of PKBs: "What should be in my PKB and what should be discarded?"

By asking yourself this question explicitly and then actually writing down the key points you practice your own judgment on what is worth remembering and what is not.

Now the added benefit of a PKB is that you can actually keep these key points in a central location and reference them in other contexts or share them with others. You are basically doing prework for later (research) questions you might have. However I would say the biggest benefit is the process; explicitly writing down what is important and discarding what is not.

For more on this subject I recommend following @fortelabs on Twitter. He does a lot of interesting writing on the subject.