Am a London controller...
As far as I can see, if you're coming from another radar controller to me (ie anything but departures straight from the tower or some other non standard situation of someone's radar not working) your mode C is presumed validated so I don't care about 'passing'. I'd just like "Callsign, descending FL XXX, heading ABC".
To try and avoid stepping on other threads, 'good morning' etc is fine presuming I'm not doing the proverbial one armed paper hangar routine.
