The change of services last year was meant to clarify and delineate the responsibilities of the pilot and the controller when under ATSOCAS. Indeed, the rules laid down are very clear for each service. BUT, some bright spark added the phrase 'duty of care' , muddling the whole thing up again, as we see from different controllers' interpretations of the rules. On asking for clarification of where duty of care lies in the sort of circumstances described above the answer from SRG was 'that would be decided in court' (in the event of a collision, accident etc). Therefore, in order to avoid being the guinea pig in court when some relatives of a dead pilot sue etc etc.... my duty of care extends to using radar derived information to pass traffic to aircraft on a basic service if i believe there is a risk of a collision or very close miss. Simple.