Modernisation?
Oh dear! Missed the point, or the comma to be more precise. The callsign of the radar controller was "xxxxRADAR", and the same was true of Approach as well as Area. That's where RADAR HEADING came from. Anyway thanks for the really useful tip on document amendments, unfortunately we don't get any at Swanwick and I have an awful job trying to remember the 467 amendments issued in the last year and a bit. By the way, I am only a "scope jockey" and I have always wanted to know why the UK has to have so many differences from ICAO. All eyes will wait with anticipation for your career-enhancing and politically correct reply.