GOA, of course Duty of Care counts. I am only offering that this particular SI (?) just makes things a little more complicated.
As in the Court of Law argument, personally I'm quite convinced that any lawer worth his salt could drive a coach and horses through the regulations. Not the same, but just look at the Ben McDui ferago.
HB.
RIS... pilot responsible for separation...
The same for RAS. The only difference being that you offer advice to maintain separation. The only time I think you may be on a sticky wicket would be if:
a. You could have been reasonably expected to notice a confliction and offer advice but failed.
b. Your advice compounded the situation.
Under the 'reasonably expected' bit, this is where, in the opinion of your peers (in court an expert witness) you should have been able to complete the task.