Cross-Compiled Linux From Scratch

I'm following the Cross-Compiled Linux From Scratch (CLFS) version 1.1.0 book for PowerPC.  I'm using this to make sure I understand what's going on with cross compilation and setting up a basic Linux system for a different architecture.

I've previously followed the CLFS book for creating x86 and x86_64 based cross compilers for PowerPC Linux at my day job, but I never really understood why I did each step in the process.  I also do not have good experience with a lot of the tools used, such as ar, as, sed, and qemu (as I don't actually own any PowerPC hardware).

My goal is to first understand the entire CLFS process and be able to either commit helpful changes back to the project or to be able to write additional documentation about how and why the CLFS project book has each step in it.  I consider myself to be a decent Linux user but there are so many widely different things that can be done with Linux that it's difficult to be excellent at all of them.

About 8 years ago I was a Gentoo zealot and through my adventures in installing and maintaining Gentoo boxes I learned a lot about Linux systems, but I wouldn't consider myself an expert [I've since reformed and I'm no longer a zealot, or a Gentoo user ;)].  I'm hoping to move closer to expert status by diving into the CLFS project and I want to be able to explain the entire process.  I think it's very important to have an understanding of how things go together to create a Linux "distribution" (in quotes because CLFS isn't really a distribution as much as a receipe).