I wouldn't recommend gentoo
as a beginner's distro. Way to throw a newbie into the deep end and potentially alienate them to linux forever
I wouldn't recommend it for someone who's never touched *nix before, but if you've installed Linux, and run apt-get a couple times, it's enormously edifying.
I never felt like I "got" Linux until I installed Gentoo.
But shouldn't that be the target audience of a "Learn to"-style guide?