Comment by danielbarla

I get the argument, and sure, it's viable in certain circumstances. But it's a few weeks _per area / topic_. In my opinion there are enough areas in a typical engine that you could study them for a year and not get through the material. There's graphics, audio, networking, physics, etc. I think the sweetspot is to understand each well enough that you have some insight into what the engine is doing for you, not necessarily to be able to (re-)implement it.