While this is important, it probably shouldn't be in beginner C book.
I understand all of it now, but had no idea about the stack or the x86 instructions, etc for years. I was still productive, and wasn't hindered.
The details can come later. Even big details like "how it works at the low level".
The most important part is to keep things fun; LPTHW was fun. For me, mucking about in assembly wasn't, and that sentiment seems like it might be common among new C programmers. Assembly has a way of slowly steamrolling your motivation.
there are a lot of C devs who don't understand what it is their code is producing, and how an application and memory are managed