Fuji Abound wrote 'Without doubt I have heard many A/G Operators going beyond their remit'
Could this be because once they have the Certificate of Competence in their hand, there is no form of regulation to ensure they 'stick' to this remit? OK the C of C has to be signed by the radio station licence holder, but there is nothing written down to say that the licence holder MUST ensure the A/G Operator is competent and maintains that competency.
ATCOs and FISOs have to have their competency checked at regular intervals by an approved Local Competency Examiner and the results of that check have to be notified to CAA/ATSD. All ATC communications MUST be recorded and the CAA recommend that FISO communications are recorded, but nothing like this exists within the AGCS.
Don't forget the CAA read these pages and by complaining about levels of service, contributors may trigger action by the CAA, either to require some sort of competency check for A/G Operators or maybe invoke the regulation that says 'The CAA can require an airport operator to provide a particular minimum level of Air Traffic Service' ie FISO instead of A/G or ATC instead of FISO.
Would you really want that to happen?