I've just mentioned in bug 105598 how I ended up missing grub for a rescue session (/ and /boot were in a raid 1 device that became degraded), and how I wished the rescue image contained grub itself, instead of relying on grub from the installed image.
How do you even get grub-install to work like this? I am stymied by this, grub-install want's the stage1 file in /usr which doesn't haven't and can't be created on RO file system.
Well, it works for me, but I didn't try grub-install, only the grub binary itself. Anyhow, the rescuecd *still* doesn't contain grub, so if things get messed up and you happen to be trying to recover from the loss of a disk containing raid members, you're just screwed. I really hope Red Hat Enterprise Linux is better in this regard.
Done, grub added to i386 rescue image.