Was Lucan right?

Gerald Harper was very famous in England long ago for playing a suave, upper class villain in a successful television series. 

He has just died at the age of 96. The Telegraph obituary quotes his insight into talking to staff.

'Always dismissing his butler with a terse “Thank you, Sutton”, Harper based his on-screen master-servant relationship on his close observation of Lord Lucan during a game of golf. “While I was chatting my head off to my caddy, there’s old Lucan waving his hand imperiously and treating his caddy as if he wasn’t there. I realised there and then the difference between acting a gent and being one.”'