For the last 40 years or so, this pensioner – still a part-time advisor to British hurdlers such as Eilidh Doyle, winner at last month’s European Athletics Team Championships in Lille, and Andrew Pozzi, who won the European 60 metres indoor title in March and, in Paris last week, ran a 110m hurdles personal best of 13.14sec - has been one of the most highly respected coaches Britain has produced.

Working primarily on hurdlers and sprinters, he’s guided the careers of John Akii-Bua, who won the 1972 Olympic 400m hurdles in a world record of 47.82, double world 110m hurdles champion and world record holder Colin Jackson, Olympic 4x100m gold medallist and World Indoor 60m champion Jason Gardener and 2011 world 400m hurdles champion Dai Greene.

He is also one of a dwindling number of those at the heart of British athletics who can directly remember the impact made upon the domestic sport by Geoff Dyson - or, as Arnold calls him, the "late, great Geoff Dyson". High praise from a man not given to the presentation of verbal bouquets.

But Arnold - who elsewhere on this site exclusively reveals to insidethegames his disquiet over the future health of British athletics, and his scepticism over the assurance of the outgoing UK Athletics chairman, Ed Warner, that he has left the domestic sport "in great shape" - now imagines Dyson "spinning in his grave” at the way in which a coaching network he spent his life inspiring and creating has been, in Arnold’s view, allowed to "dribble away down the drain".

Yes, Arnold believes the upcoming International Association of Athletics Federations World Championships in London are going to be a success. Over a million tickets have been sold. People are putting their money down, drawn by the prospect of watching Usain Bolt sign off on his championship career, of Mo Farah defending his 5,000m and 10,000m titles in what will be the last track races of his career in his home country, of the new rising talent Wayde Van Niekerk of South Africa testing himself with a prospective 200m/400m double.

It is on the other side of next month’s athletics jamboree in the Olympic Stadium that Arnold - national coach from 1994 to 1997, and national event coach for hurdles at the University of Bath from 1998 until he finished his contract in December last year – fears for the domestic sport’s future. For him, it’s all about the coaching infrastructure - or lack of it.

"Coach education has now been downgraded to coach qualification,” he says. "The process is too expensive, especially for our cherished brigade of volunteers. The process is little more than going online, studying online, answering questions online, then having one day with a human being to complete the process at level three.

"Level four coach education - the former senior coach award) - the highest that could once be obtained in the UK, has not happened since 1998. Access to good mentors is rarely possible, especially if you live in far flung parts of the UK.

"Former top-class athletes are rarely encouraged to enter our scene as coaches or mentors. Such a waste of resources.

"I once had the privilege of working in proper coach education, with men of the calibre of Frank Dick and Carlton Johnson and many other professional national coaches.  The late, great Geoff Dyson must be spinning in his grave. I doubt if many of our UKA leaders have ever heard of Geoff Dyson?

“That brings me to another question, which I have put to Neil Black, our performance director, on many occasions without answer. The question is - 'Who leads coaching in the United Kingdom?' The answer currently is no one!

"We do not have anyone who acts as head coach to the British team and we do not have anyone of sufficient expertise to lead coach education at the highest international level."

Arnold added:"That situation has obtained since Charles van Commenee returned to Holland in 2012.

"Athlete Development is at a low ebb. We still see outstanding young athletes floundering in that crucial period between the end of the under-20 group and their 25th birthday. We are slowly losing coaches who have expertise in this area. Athletes are left to sink or swim with inexperienced coaches. Many are sinking.

"Niels de Vos was appointed chief executive of UK Athletics in 2007. Soon after his appointment, he invited me to sit with him and discuss the state of the sport in the UK. Within the discussion, I pleaded that he should never neglect coach education and coach development, but most importantly UKA should never neglect athlete development.

"Nowadays, it seems that the UKA hierarchy have decided to marginalise professional and volunteer coaches, who along with our brilliant officials are the bedrock of athletics in our country. Whilst there are still outstanding coaches, our coaching expertise is slowly dribbling away down the drain."

In 2009, a year before he died, Tony Ward – the former level 4 coach, co-founder of the British Athletics League, writer, announcer and press spokesman for the domestic sport’s governing body - wrote an article about Dyson on his excellent blogpost, Track Chat.

He recalled speaking to Tom Tellez, who coached into Carl Lewis at the University of Houston the impeccable sprinting and long jumping technique that eventually earned him nine Olympic gold medals, on the subject of Dyson.

"At the drop of a hat Tellez would produce a well-thumbed book and cry 'this is my bible!’,' wrote Ward. "A book, written some 20 years before he was coaching Lewis, by an Englishman, G.H.G. Dyson and entitled the Mechanics of Athletics. Tellez told me, 20 years ago, that he had read it perhaps 50 times. 'If I have had success as a coach I owe a great deal of it to Geoff Dyson,' he said. 'His book started me on the trail of discovering the real facts about track and field'."

Ward added: "It is somehow symbolic to me that the Mechanics of Athletics is out of print, symbolic of the fact that the scheme that Dyson conceived 60 years ago, that became the envy of the world and was re-constructed in Canada, has been desecrated over the last decade or more by those who don’t know what they don’t know.

"He conceived of the idea of a team of national coaches who would ‘teach the teachers and coach (my italics) the coaches’ in the different regions of Britain. I think the mantra was deliberate. Teachers would be taught but coaches would be coached in the art of applying the science they had gained.”

Well, the University of Bath’s athletics operation has been largely closed down now. All roads lead to Loughborough. As Arnold is at pains to point out, there are still some very good coaches around. But as for the structure…

It’s a view that deserves respect and attention.