Hadn't realised that this thread was still active, how time flies when you are retired.
Here is another issue to ponder, the term "control" is something of an anomaly. If a flight is VFR according to ICAO it is not a controlled flight unless operated in Class C airspace whereby it becomes a "controlled VFR" flight and ATC are responsible for providing separation between IFR and VFR, something that this thread has illustrated to be the case in UK Class D airspace.
As the UK is increasingly anxious to align itself to ICAO Annex 11, PANS ATM Doc 4444 and all things ICAO (Single European Skies approaching?) may be its time that AATSD sorted this out and formally required what they apparently have been pressuring ATCOs to do in Class D, ie separate VFR from IFR. Have seen too many former colleagues hauled over the coals after providing precise traffic information to IFR on VFR, no risk of collision, TCAS RA, ATCO suspended and criticised for not separating.
Time for Class C CTA and CTR in UK?