I wrote about this in my 2018 biography of Thomi Keller, the long-time President of FISA, the acronym by which World Rowing was known throughout his three decades at the helm.

It seemed to me that Keller had done little to promote expansion of women's rowing in the early years of his FISA Presidency, which began in 1958.

By the late-1960s, however, his attitude has been transformed and, once convinced, as I put it, "he set about pursuing the cause with typical vigour".

One thing which I felt I never satisfactorily nailed was what exactly triggered his change of heart - even if, as I wrote, it coincided with the election to FISA's Technical Commission in 1968 of Claus Hess, a West German official who was both a strong advocate of women’s rowing and a close Keller confidant.

So I was pleased to receive an email earlier this year from a former United States oarswoman called Ernestine Bayer which shed new light on the subject.

I have found that the receipt of such occasional, illuminating correspondence from readers is one of the chief delights of writing books.

Bayer told me about an episode in 1967 when the globe-trotting Keller had visited St. Catharines in Ontario to review progress ahead of the 1970 World Championships.

According to Bayer, a Canadian official and oarsman called Craig Swayze had invited the Philadelphia Girls' Rowing Club (PGRC) to St. Catharines for an exhibition race, in the hope of generating interest in the sport among Canadian women.

The rival eight in the exhibition race was, Bayer said, comprised of "retired male Olympic oarsmen - including Thomi Keller in the number six seat".

The event was in conjunction with the first North American Rowing Championships on a newly-created course on the city's Martindale Waterways.

The PGRC women’s eight was a powerful crew who had "just returned from California where they had swept the heavyweight events at the second women’s national championships, successfully defending their 1966 title".

Bayer goes on: "The 500-metre exhibition race ended in a dead heat.

"After crossing the finish, the men nestled their eight next to the PGRC eight and exchanged a kiss with their seat partner in the other boat.

"What happened next changed the future of women's rowing for ever.

"Thomi invited the women's crew to the referees' reception that evening."

At this reception, Keller struck up a conversation with Ernestine "Ernie" Bayer, manager of the PGRC women's crew and my correspondent’s mother.

After hearing about the Philadelphia crew's remarkable performance in California, the FISA President smiled and did something unprecedented: he issued a personal invitation to the PGRC women to attend the 1967 European Rowing Championships a few weeks later in France.

As Bayer explained in her email, Keller’s words - "I want your girls to come to Vichy" - changed the future of women's rowing.

This was a time when women’s crews did not compete in the sport's World Championships, which had started only five years earlier as a quadrennial competition.

Keller's invitation was therefore potentially opening the door for US oarswomen to enter international competition, then dominated by East European athletes.

There were obstacles that would have to be speedily overcome, however.

According to Bayer, her mother had to explain to the FISA President that permission to do just what he was suggesting had already been turned down.

"On returning from the Nationals, Ernie had approached the United States FISA representative, John Carlin, for permission to enter the European Championships and been denied," Bayer told me.

Moreover: "Each crew member paid her own expenses; they did not have the money to make the trip."

Keller, characteristically, would not be put off.

"Ernestine, I’ll take care of John Carlin, you take care of the money," he retorted.

Keller also helped to ensure that Bayer was able to complete and hand in the necessary paperwork in the two hours remaining before entries closed.

At a meeting of the crew the next day, a vote on whether to go to Vichy was taken.

Perhaps swayed by Bayer’s advice that "some of you will never have this opportunity again, you should take it", the verdict was five-four in favour of making the trip.

Horace Davenport, a former rower who had founded the US National Rowing Foundation the previous year, secretly loaned the team the money to finance their costs.

Bayer tells me that each team member paid their $600 (£510/€600) loan back within a year.

The PGRC women accordingly went to Vichy, hence becoming the first US women's crew to compete internationally.

Bayer argues, I think convincingly, that the "historic" exhibition race in which he took part in Canada helped to change Keller’s future vision for women's rowing and set the stage for the six women's rowing events to be added to the 1976 Olympic sports programme.

As a postscript, she tells me how Keller helped her to source a shell direct from a member of the boat-building Stämpfli family when she needed to lease equipment to compete for the US at the 1969 European Championships at Klagenfurt - "If I remember correctly she arrived at Klagenfurt with the boat strapped to the top of her station wagon".

She also reveals that the women from that ground-breaking PGRC crew who competed at Vichy are to be admitted to the US National Rowing Foundation's Hall of Fame in October in Boston.

It seems a fitting and very timely tribute.

Nine years later, US women took two of the 18 medals at that inaugural Olympic women’s rowing competition.