David Cameron’s surprise appearance at the Blenheim Festival of Literature, Film and Music was a significant coup for the organisers of this prestigious annual event.

Well, perhaps it wasn’t such a surprise for everybody; the programme had referred, after all, to a visit by “one of Britain’s most prominent politicians”. Who better fitted the bill, with a ‘gig’ on home territory, too?

No one doubted what an honour it was to have him there, and especially the festival’s patron, the Duke of Gloucester. The star guest was gracing the inaugural Duke of Gloucester Lecture.

This was the first time I had seen the duke ‘in the flesh’, incidentally, in more than four decades. I was among the members of the press who covered his wedding to Danish-born Birgitte van Deurs at Barnwell, near Oundle, in July 1972.

At the time, he looked destined to live out his life as Prince Richard. The death a month later of his older brother Prince William altered all that. The plane crash that killed him was reported, I will always remember, during a motor racing event at Brands Hatch whither I had travelled with a number of people who knew the prince from Northamptonshire farming circles. Their shock was palpable.

The beaming Prime Minister looked every inch a winner last Friday as he dealt with the intelligent questions from interviewer Lord (Peter) Hennessy. I suppose this might have something to do with ‘the Corbyn effect’, the effect on David Cameron, of course, being the demonstration from evidence now supplied, as comparisons are made, that he alone has what it takes to lead our nation.

Perhaps not wishing to trespass into areas of private glee, Hennessy asked no questions about the current state of the Labour Party.

Nor, at the end of a week of sensational revelations – sensational cobblers, in my view – was anything said concerning the biography of the PM by Lord Ashcroft. This is a work of alleged revenge for Cameron’s refusal to let him donate his way into office.

The incident that lead to the most lurid headlines was Cameron’s alleged initiation ceremony on becoming a member of Oxford’s exclusive Piers Gaveston Society, named for Edward II’s catamite (presumed) and known for behaviour in outrageous style.

That the story was hokum was apparent to anyone who knows anything of the society, in which group I can include myself.

The society’s founder Valentine Guinness, whom I knew during his student days, was among the first to point out that since the society has no membership it is absurd to talk of initiation ceremonies.

The Gaveston simply arranges parties, to which people are invited. In the early days I was summoned to a number, which only shows how lacking in exclusivity these gatherings were. One invitation specified the dress to be ‘Roman camp’, which indicates the aura of affected decadence attached to proceedings.

Among the regular attenders was the exceptionally handsome Hugh Grant. At other times, he might have been found enjoying a game of darts with me at the Waterman’s Arms (now The Punter) on Osney Island.

Here, too, has been seen Mr Cameron on two recent occasions, though food rather than ‘arrows’ has proved the draw.

Returning to Blenheim, I must not let this column close without a mention of one of the key festival events, as it seemed to me. This was the visit of Dr Maki Mandela, the eldest daughter of Nelson Mandela. She was there to talk of her father’s life and legacy.

In delicately-handled questioning by South African journalist John Battersby, she skirted such painful topics as the death of her siblings. Of the controversial figure of Winnie Mandela, who followed Maki’s mother as Mandela’s wife, we were told, somewhat diplomatically, that she was “a loose cannon”.

Asked about her famous father’s principal legacy, Maki spoke of his inspirational capacity for forgiveness, in looking towards a bright future and not dwelling on the traumas of the past.

“I am not religious, but I am very spiritual. I try to be a better person today than I was yesterday.”