As I follow the installation path set before me. I do have issues with setting up systemd and gnome. To start with, I mm glad to see a reference kernel source files. Problems I came across while's t installing systemd. Almost all requested changes were fine. But the support for eBrf shown in the manual is missing from the dialog/menu. using the systemd grub installation, there is no method to shown how to install grub before 'mkconfig-grub' By the way.. Before editing /etc/default/grub. A method for creating "etc/default/grub" directory needs to be defined. And before you jump down my.. Review CAREFULLY the documentation for both installation 'till systemd split and the systemd grub installation. Better yet, forget all you know about gentoo, and do a line by line installation of Gentoo and Gentoo Systemd with grub.
If it's the wiki you are talking about, then do remember it's a wiki: you can change it yourself.
*** Bug 673150 has been marked as a duplicate of this bug. ***