"EFI install from DVD forgets previous EFI boot"
"As far as sharing the same /boot/efi directory between installs, we don't
support that -- a new copy of the grub.efi binary is written as well as a new
In a related case, anaconda states again that shared, merged grub.conf for EFI
booting is not supported:
"upgrade using boot.iso destroys EFI boot"