When dealing with the excessively rich and privileged, you've got your two basic approaches. One is to go in hard and deliberately working class. A regional accent is always a plus in this. Seawoll has been known to deploy a Mancunian dialect so impenetrable that members of Oasis would have needed subtitles, and graduate entries with double firsts from Oxford practise a credible Estuary in the mirror and drop their glottals with gay abandon when necessary. That approach only works if the subject suffers from residual middle-class guilt - unfortunately the properly posh, the nouveau riche and senior legal professionals are rarely prey to such weaknesses. For them you have to go in obliquely and with maximum Downton Abbey. Fortunately for us we have just the man.