Which is why I have a pervading sense of déjà vu as Rio 2016 fast becomes a golden memory and we look forward to Tokyo 2020. For this is where I came in.

Tokyo 1964 was the first Olympics I covered, a Games which remains etched in the consciousness as the last of what we might term the ‘pure’ Olympics, untainted by terrorism, boycotts, body searches, corruption or other assorted scandals. Certainly the most hassle-free of the dozen I have attended.

And the only drugs we encountered were an aspirin or paracetamol the morning after imbibing a saké or two too many.

Yet they were not without controversy, largely because Japan had been awarded the Games less than 20 years after the end of World War Two and memories of the atrocities committed in the name of that enemy nation lingered in the memory.

My late but then newly-acquired father-in-law was aghast that Tokyo should be the Olympic destination. “You’ll hate the Japs, nasty little bastards,” he warned me before I left for Tokyo.

He had good reason to loathe them, having been their guest as a POW for almost four years in the notorious prison camp at Changi in Singapore, and working on the Burma Railway.

But he was wrong. I don’t think I encountered a Japanese I didn’t like. They were charming, dignified and welcoming, apparently determined to show that times - and their culture - had changed.

No-one played political Games and perhaps for the last time competitors seemed to reflect the Olympic ideal that it is not so much the winning, but the taking part. Baron Pierre de Coubertin was surely smiling down on them benevolently.

It is highly doubtful whether such purity of sporting spirit will prevail in four years, as the Olympics have changed darkly beyond anything that Tokyo 1964 would recognise.

For one thing, there are pros involved now - plus quite a few cons. In the Games I have covered since I have seen the Olympics manifestly outgrow anything that Tokyo could have offered them over half a century ago. They have become over-commercialised, unwieldy and too easily corruptible.

Then there was a simple, innocent, charm about the 1964 Games that has never been totally replicated, no doubt because the Olympic bandwagon has rolled deep into too-frequently malevolent territory, beginning in 1968 when the Mexican Government ruthlessly gunned down protesting students in the notorious Plaza of the Three Cultures and the International Olympic Committee (IOC), not for the first time, suddenly developed a case of myopia.

Mexico City followed up with the Black Power demo by Americans Tommie Smith and John Carlos. Four years earlier in Tokyo the only black and white issue was the fact that this was how the Olympics were viewed on our television screens.

Munich brought the Israeli massacre, Montreal, Moscow and Los Angeles were winged by boycotts and then in Seoul a red-eyed Ben Johnson injected drugs into the Olympic bloodstream where it has been coursing virulently through the veins ever since.

I missed Atlanta as I was sports editing a national newspaper (some say I wasn't a bad judge) but Barcelona had been pleasantly good and while all had a few hiccups and controversies along the way Sydney, Athens and, of course, London were eminently enjoyable.

So, especially from Britain’s record-breaking perspective, was Rio. But for me Tokyo 1964 remains the Olympics’ role model.

I sometimes still hum the catchy jingle that woke us every day: "Good morning, Tokyo, happy to be greeting you".

These really were a happy Olympics, especially for Britain, who collected 20 medals overall with long-jump golds from Lynn "The Leap" Davies and the original golden girl, Mary Rand.

Plus there was outsider Ann Packer's shock triumph in the 800 metres and the poignant moment when the wife of the walker Ken Matthews dashed onto the track to embrace him as he crossed the line.

It rained quite a lot in Tokyo but no-one seemed to mind. The Games were held late in the year, between October 10 and 24, and the last lap of the Torch Relay from Olympia to light the flame was poignantly run by the 19-year-old Yoshinori Sakai, a young athlete born in Hiroshima on the day of the atomic bomb.

No politics in the last of the Olympics Summer Wine, but a future eminent politician played his part. Menzies Campbell, later to become Liberal Democrat leader, was a former rugby winger whose fleet-footedness translated into sprinting for Britain in Tokyo.

Now Sir Menzies, 75-year-old "Ming" typified how different those Games were to those that followed. 

"They were free of drugs - at least we assumed they were - and it was before commercialism set in," he told insidethegames. "Adidas gave us a pair of spikes and a pair of warm-ups and if you were lucky you got a bag.

"Most of us had only run on grass or cinder tracks and I remember the team captain, Robbie Brightwell, looking at all those wonderful facilities there and saying to us: 'There are only two ways to compete here - be a total scrubber or go home with a gold medal.'"

Ming didn't win gold but he was never a scrubber. His 10.2 seconds for the 100m was a British record that lasted for eight years and he once broke a 53-year-old record for the rarely run 300 yards. The year after Tokyo he was appointed British team captain.

Swimmer Anita Lonsborough, a gold medallist in Rome four years earlier, carried the British flag, but it was the Stars and Stripes that fluttered most triumphantly in the Olympic Stadium.

Bob Hayes, one of the fastest men ever seen, returned the 100m sprint title to the United States and his compatriot Billy Mills surprisingly defeated Australian favourite Ron Clarke in the 10,000m, becoming the first Native American to win Olympic gold.

The 5,000m was also a sad affair for the demoralised Clarke, who finished fourth to another American unknown, Bob Schul.

There were other shocks too, but one of the biggest was how comparatively easy it became to gain access to the Olympic Village. In Tokyo, there was no hype, and no hassle either. Getting into the Village was a piece of cake - or rather, a bottle of gin.

I should explain. Tokyo's Olympic Village was not the maximum-security compound that others, by necessity, later became. No scowling armed police or heavy-handed militia. Just one charming chap, booted and suited in civvies, checking passes at the gate.

However, entry to journalists was restricted to certain times, not all of them convenient for our deadlines. Although he spoke little English, our benevolent gatekeeper chum always seemed pleased to see us. We gathered he had a liking for all things British - not least, Booths Gin.

One of us happened to have a duty free bottle that we decided to present to him as a goodwill gesture, much to his delight.

From then on whenever we wanted to interview any of the athletes inside the Village he would motion us through without any check, bowing low as he smilingly murmured: "Ah, Booths!"

It was during such a Booths-facilitated excursion that I had one of the most memorable encounters of my career, becoming the first man to put a future world heavyweight champion on the floor.

I was wandering through the Village when, hurtling around a corner, pedalling furiously on a bike, came this large American with the biggest thighs I had ever seen.

He swerved to avoid me and promptly fell off.

He looked the aggressive sort so I gulped and swiftly apologised. "No, problem," he replied, dusting himself down. "My fault. Shoulda looked where I was going. You okay fella?"

Thus, I became the first man to put Smokin' Joe Frazier on the floor.

Fortunately for me the late Joe, who went on to win the Olympic heavyweight gold and the World Heavyweight Championship, wasn't smokin', just smilin' as he remounted and went on his way.

And so the Olympic Rings have turned full circle. But my 2020 vision is far removed from the innocence of my first Olympics in the land of cherry blossom, and the ever-rising sun.

I have no doubt Tokyo will do a superb job as second time round hosts. But it cannot be the same as the class of  ’64.