Oops...my answer was incomplete. Belatedly, I realized that the Recovery HD's dimmed state in DU's left-hand pane meant that it wasn't mounted. Upon mounting it, I find that it does indeed appear under Devices in a Finder window sidebar.
Could it be that once mounted by the user, the Recovery HD is mounted on successive reboots until unmounted by the user? I'm not ready to reboot at the moment, but I'll experiment next time I do.
