Doesn't LVM2 work by finding indexes and volume signatures and the like on disk, rather than in configuration files? Aren't the configuration files there to help recovery in case of disaster, not for normal use? I've definitely used multiple Debian systems (like testing and stable) with the (some of) same LVM partitions on the same machine and never had problems -- but then, the Debian default configurations may always just happen to be the same.
I currently have dual boot with Windows XP and Debian testing. I'm considering adding funtoo to the mix, so I have an escape hatch should systemd become intolerable. Can I share the /home between the two systems? Or will that lead to indescribable chaos? -- hendrik