Is this bug report worthy?
Maybe, but I wouldn't be suprised if nobody runs to fix it.
In its current form - I don't really see Fedora/RedHat software raid as being a complete RAID 'solution' - without having the ability to disconnect either disk and instantly boot from the other ...
Use LILO instead. If you choose LILO as your boot loader during install, Anaconda will install it on both disk drives (if your boot partition is mirrored). Actually, Anaconda will just write correct LILO confing file, and LILO itself will install correctly (if you have for example "boot=/dev/md0" in lilo.conf, LILO will check what md0 is, and install itself to all submirrors of md0).
This issue with Grub is the primary reason I'm still using LILO. I kind of got tired of fixing it on each and every install I'm doing (well, I automated it as part of postinstall script in kickstart configuration file, but still liked LILO built-in understanding of mirrors better).
And anyhow, if you are not in fancy graphics, and/or don't have really complicated boot configuration, there is not any advantage of using Grub.
Should I file a bug report?
Doesn't cost you a thing to try. But first check if somebody else reported it. It is such an old issue that it is very likely there's already bug report for that. If you decide to report it, my personal opinion is that this is something that should be delt with in Grub itself, not in Anaconda installer. Grub should be made aware of mirrors (just the same as LILO is aware of mirrors), and install itself automatically on all submirrors.
-- Aleksandar Milivojevic <amilivojevic@xxxxxx> Pollard Banknote Limited Systems Administrator 1499 Buffalo Place Tel: (204) 474-2323 ext 276 Winnipeg, MB R3T 1L7