Additionally: In section C.4.1 and/or C.4.3 it should be mentioned that you want to mount partions destined to become /usr, /var, etc to /mnt/debinst/usr, /mnt/debinst/var, etc before running debootstrap on /mnt/debinst. If you don't do this the result is wrong and you have to move the file system under /mnt/debinst/usr, /mnt/debinst/var, etc to the partitions by hand.