DubTrub
Agreed "copy" is not CAP413 nor 493. American cop programmes have a lot to asnwer for! I believe "copy" was used in WWII and for a short time after by radio operators in that they had to physically "copy" i.e. write down, the full message in their radio log. (Of course, it could be correct UK phraseology, contained in an ATC manual somewhere!)
As for the taxi clearance. Perhaps it's a misunderstanding, so I'll rephrase. If operating from an aerodrome with an A/G service, I would not push the button and say that I was taxiing, without establishing comms with the A/G station. It's poor airmanship! If I did not get a response after my initial call,
then I would call "taxiing for RWY..." As
Jonathang has copied an excerpt from the 413, it is clear to me, that the "typical" conversation should start with an "inital" call. Agreed?
As for "negative". Why not help the pilot out, who may not be fully conversant with the procedures, by using "G-XX, Station Radio, Roger, unable to provide (taxi) instructions; runway, left hand, QNH etc". You are still providing a
service, albeit A/G. Every little helps!
Sometimes "roger" is the only word in an A/G Operators vocabulary. And yes, I do hold a bit of paper that says I'm an A/G Operator.
Our posts overlapped, me thinks.