My system was minimal install, so many language support must be drag in by some strange requirement. However, the main problem is removal of some groups. I tried remove some really strange: yum groupremove "Venda Support" "Inuktitut Support" "Kannada Support" which try to remove OO and some others. http://pastebin.test.redhat.com/12602 And weird things about groups are also here: yum groupremove "Electronic Lab" which ends with removal of qemu http://pastebin.test.redhat.com/12603 If I installed qemu package then I don't anticipate installation of Electronic group. I suppose the group shouldn't be mentioned as installed, in case one package from group was installed. Also the bunch of language support doesn't make sense.
I think the problem is in how yum handles groups. If you have a single package from a group installed, that group is considered as installed too. This is IMO bad. The group list doesn't match with groups installed by anaconda. Yum should make difference between yum install package vs yum groupinstall group (or yum install @group).
No, that's not how yum handles group. If a group has NO mandatory and NO default pkgs, then any optional pkg installed marks the group as installed. if a group has NO mandatory pkgs then if all of the default pkgs are installed then the group is installed if a group has mandatory pkgs then only if all of the mandatory pkgs are installed then the group is installed. yes, we know the groups concept is sub-optimal but the sets of ways to change it are limited.
This is as designed as Seth described.