10w in general I agree with nearly everything you say, for my particular event it comes back to my perception of being "forced" onto a collison course by ATC, having my attempts at applying vertical separation refused, with the consequence that, rightly or wrongly, I felt I must comply with the clearance until the point where doing so would have caused a collision and thus had to take "emergency" action rather than earlier action that would have been more comfortable.
I asked more TREs at work what Radar Control Service for VFR meant, none of them really knew and they had similar ideas to my original feeling that it gave some degree of safety / separation from other traffic. So it's primarily for that reason that I have now filed an Airprox.
HC