Whats the problem with using the word currently though? When Malcolm G O Payne said you are either there are you aren't doesnt really make sence to me, as you are constantly moving. It seems logical to say I am currently over a position, because by the time you've finished saying "exactly" where you are/were, you are no longer there. Think Malcolm G O Payne is being a little too picky, which is probably good as he is an examiner and to teach/examiner to the correct standard, but can't for one second see it ever being a problem when talking to a ATSU.
Agree though, that when giving a responce like that, callsign should follow your answer.
HB