There's no explanation on what 'chrooting' is all about. A paragraph introduction should do the magic. Reproducible: Always Steps to Reproduce:
Maybe there should also be a complete paragraph exdplaining what Linux is (for first time Linux users)
About chrooting, we say: Now that all partitions are initialized and the base environment installed, it is time to enter our new installation environment by chrooting into it. This means that we change from the current installation environment (LiveCD or other installation medium) to your installation system (namely the initialized partitions). This chrooting is done in three steps. First we will change the root from / (on the installation medium) to /mnt/gentoo (on your partitions) using chroot. Then we will create a new environment using env-update, which essentially creates environment variables. Finally, we load those variables into memory using source. About the "What is Linux" stuff, I've been thinking about something similar as well, but I am still wondering if the Gentoo handbook is the right place - it's not Gentoo-specific after all.
That's right ... but ... when I read the paragraph header ie 6a chrooting it took me 4 more subparagraphs to figure out what it meant. I asked my wife (we're dutch) ... what means 'chrooting' as if it was an english word and not an acronym of change root. There's no need for a real newbie elaboration but the term was new for me. BTW: It's nice to see this kind of quick bug pickup time ;-)
Fixing the fact that it's that many paragraphs down below might decrease the readability imho. It would first explain the word "chroot", then say something along the lines of "but before we do that, we blablabla", after which it would say "Now that foobar is done, we can chroot". I'm marking this as wontfix - if the explanation was in a totally different section (outside the "Chrooting") I would update it, but I believe it's safe to assume most users read the entire chapter :)