SASless, I take your point about the amateur rescue aspect - I have been involved in similar scenarios at sea. But. This would seem to be a case of a pilot hearing a MAYDAY broadcast, finds himself in the area, has a look, sees the casualty with no-one in assistance so he does the right thing in landing and assisting.
Granted, ferrying the para may be an issue, caught up in the moment etc. but certainly responding to the initial request for help should be assumed duty no?
CP sounds like a T*T IMHO. There are bound to have been easier ways to deal with the off course aspects of this.