This domain is unique in that it's not a good idea to read.
crazy talk.
Sure, learn by doing; but there are great resources to help you understand far, far faster than you ever will by experimenting alone. If nothing else, there is good code to read, and classic texts.
Mmhm. As with everything, it's a balance. It's important to understand that reading is one of the most effective forms of procrastination that has ever been invented. It's also the prism through which your entire future passes, but everyone already knows that.
For example, Carmack was able to "invent" BSP because he was (as far as I've heard) an avid reader of medical journals. Specifically, journals and papers about the graphics techniques they used at the time. The field of medicine turns out to be very lucrative for an ambitious graphics programmer, because they're often at the frontiers of what's currently possible. So apparently BSP was used in accelerating medical renderings, and Carmack was able to see their potential for realtime graphics. The only reason he was able to do that was by reading pretty much every possible thing.
None of that will help you unless you force yourself to do and not read, though.
You stated "This domain is unique in that it's not a good idea to read."
This is just not true in either of its claims. It's not even useful hyperbole, really, it's just wrong.
Graphics programming is exactly like other domains of technical development, you will learn best by a combination of reading good summaries/examples of what is known, doing work on your own (not cutting corners), and talking to people that know more about that you do.
And yet, if you proceed as if it were correct, you'll be amazed at what you'll accomplish. The comment I was replying to was essentially asking, "What would've helped you back when you were in my position?" Ten out of ten times, I'd choose to tell myself, "Stop trying to read about how graphics engines work. Figure out how to get triangles up on the screen, without copying someone else."
The best I can say is that my career began from that method. And by asking a lot of questions on IRC.
Glad it worked for you, but that doesn't make it good advice. And doesn't change the lack of uniqueness. It's usually a mistake to generalize from your own experience, when thinking about pedagogy. I'd wager that most people would do ok following that advice as if it were true ... But not as well as if they'd read as well.
Sure, learn by doing; but there are great resources to help you understand far, far faster than you ever will by experimenting alone. If nothing else, there is good code to read, and classic texts.