Terrain clearance
 

Recently I have heard several ATCOs giving pilots instructions along the lines of 'maintain terrain clearance' which seems to be something new.

Is it something imposed on them by the EU (like the Hectopascal), stating the bleeding obvious (don't hit the ground), or is it rather more useful than that?

Here it means you are being taken below the MSA or MVA so yes it does mean don't fly into anything.

It is also to protect the agency/controller so that if you do fly into something we cannot lose in court since we 'told' you. Remember, all rules and required phraseology were written by lawyers. :8

Not a new thing, at least not when operating in class G airspace. Something like this is often said to a VFR pilot who chooses to fly at low altitude and not receive a radar service; usually something like 'terrain clearance is your own responsibility'.

If you are being provided with a Traffic Service and are, or elect to descend below the MSA, then a Terrain alert is given along the lines of "taking your own terrain clearance"

"Terrain
Subject to ATS surveillance system coverage, Traffic Service may be provided below ATC unit terrain safe levels; however, pilots remain responsible for terrain clearance at all times. Other than when following a notified instrument flight procedure, a pilot requesting to descend below the ATC unit terrain safe level shall be reminded that he remains responsible for terrain clearance."