Lukas Sandström [off-list ref] writes:
The "git-repack -a -d" case is fixed in Junios master, and I have sent out
a patch which lets you pipe git-fsck-objects --full --unreachable to
git-pack-redundant in the other cases, so the problem should hopefully
be resolved shortly.
After thinking a bit about it, I tend to agree with what Linus
said, and would vote for the simplicity of the older way. From
usage point of view, git-repack is primarily about repacking,
and the -d option is a funny exception applicable to -a case,
only because it is so obvious (i.e. after repacking everything
into one, it is obvious any other packs are unneeded). We might
even want to make the "-a" flag to imply "-a -d" there.