Explain how to access HD when it's a LVM volume
doc/encryption_and_privacy/your_data_wont_be_saved_unless_explicitly_asked.mdwn -> the note about LVM being “more complicated” could be explained.
Pertinent discussion from #5636 (closed):
Regarding LVM, what happens by default?
-> Nothing useful when a PV appears (e.g. after unlocking a dm-crypt volume that hosts a PV).
what happens if you run vgchange -ay?
-> Then the VG and all LVs in there appear. Maybe they can even be mounted from GNOME Disks (not sure).