It does use incremental builds so long as you don't reset everything.

I'm not sure that a lot of people who don't work with make realize that it's smart enough to only rebuild what has changed, and that it's not just a command runner!

A bit out of date, but not to the point of being useless. I still give them to juniors and interns that want to learn more about kernel work. There's also a much more recent (2022) book called Linux Device Driver Development published by packt. In general, these sorts of books are mainly useful for "what not to do", as general architecture stuff is usually well documented by source code examples and in-kernel docs.