[lapcat]

> in Recovery Mode, Terminal does require mounting the data volume first, which typically prompts for an admin password.

This is not my experience. The Data volume mounts automatically, and there's no password prompt.

[AshamedCaptain]

I concur, that is the normal behavior without FDE. But besides, you can still use the Terminal of _any_ other bootable OS X disk, not just the recovery itself. With FDE, neither of this will work.