One could use a "labelindex" option in addition, to select between identical LABELs. I've implemented this on my system there are 2 identical root filesystems on disk so that on upgrade the unused one is written and booted to. The patch to mkinitrd to support this is attached. Note by having 2 root filesystems (in conjuction with a hardware watchdog, and the savedefault --once option in grub) allows one to construct a system that is much less likely to ever hang, as it can failback to the origonal root partition that it was running.
The latest version of lilo (22.6) allows root=LABEL=blah in the config file
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