However, it is my opinion that having a project posted on HN, being directed to look at the "internals" of another software project (such project being licensed under the GPL), and subsequently modifying your own project with what you've learned, is legally risky.
Specifically, if I were corporate counsel at a company looking to use MIT-licensed code in a product of ours, and our due diligence uncovered that just such a thing had happened, I would advise against using that code. The risk—that is, likelihood multiplied by the magnitude of the severity of the consequences—of being compelled to license our software under the GPL would be far too high.
As a result, I stand by my assessment that it is probably best—albeit not mandatory—for the OP author not to take a look at how GPL'd code accomplishes what OP author is trying to accomplish.