he is probably dead posh.
only really posh people speak like that, and they are very few in the uk.
i actually only met one person who spoke like that before and that was an awful headmaster at school who upset me many times.
so, unfortunately i have to read his writings as i can't listen to him!
he just sounds like someone making fun of a very extremely posh accent and i feel like i should laugh when i listen!
his writings are very good, i just hope i don't hear him give a lecture live, at least till i got over the shock about the accent and practiced many times listening at home without laughing.
by the way, i feel similarly about texas accents. there was some preacher my friend was listening to on the internet and i nearly laughed coz i thought he was joking! i didn't realise there were real people who speak like in the cowboy movies, i thought it was all a joke!
in case u wondered, lots of people laugh at my accent, coz i pick up a bit of an accent from everyone i meet, and as most of my friends don't speak very good english, i sound like an indian who was imprisoned in egypt for many years and then lived for at least 20 years in eastern europe without any access to english speaking people.