It is an image which says it all about Captain T A Forster. Loyalty, longevity, heaps of winners - and on closer inspection, no doubt, the great majority were chasers. As Sumner says, "as far as he's concerned, there's only one thing worse than hurdle racing, and that's Flat racing".
It is fences or nothing for the Captain, so much so that it is impossible to imagine anyone else's initials on Dublin Flyer's saddlecloth. Physically, the 11-year-old is magnificent in every detail, tall and athletic, and so robustly put together that you could picture him carrying a 17-stone Hussar. When he tackles Cheltenham, the ultimate test of a chaser, it is one of the most glorious sights in sport, a fearless exhibition of foot-perfect jumping. Quite simply, he and Forster were made for each other.
"The Captain knows him inside out," Brendan Powell, Dublin Flyer's jockey for the last four seasons, says. "He's quite excitable at home and if he'd gone to a lot of places, he might have been over-raced as a young horse and would probably never have been the horse he is now. The Captain brought him along slowly with just a few runs in hurdles and then it was straight to fences. He never abuses horses, and he'll always get the best out of one like that."
But it all takes time, and these days there are very few trainers who are ready to be as patient, or owners who are prepared to let them. Even Sumner admits that "over the years, we've criticised him for not running horses enough," before adding that, "with hindsight, he's always been right".
Sumner has been sending horses to Forster almost from the moment he took out a licence in 1962, and the pair won both a Hennessy and a King George more than 20 ago with Royal Marshall II. As yet, the Gold Cup itself has eluded Forster, but he has saddled three winners of the Grand National, most recently in 1985, when Last Suspect carried Hywel Davies, in the Arkle colours of Anne, Duchess of Westminster, to victory at 50-1.
The trainer's pointed advice to Davies as he legged him up beforehand - "keep remounting" - is racing folklore. Apart from his devotion to steeplechasers, pessimism is the other thing that Forster is famous for, and it is not mere affectation (putting on a show for the cameras, after all, is hardly his style). "He really is like that," Henry Daly, his assistant for the last eight years, says. "Everything will get beat as far as he's concerned, everything will go wrong, and it means when something goes right, he's pleased and surprised. It's just his way and he'll never change, ever."
Yet it was hardly the action of a pessimist when, with his 60th birthday fast approaching, Forster decided to move out of the Wantage yard which had been his base for three decades and start from scratch at Downton Hall estate, near Ludlow, where to begin with there were not even any gallops, just endless acres of green fields.
"I think he wanted a new spark in his life, and it came at just the right time," Sumner says, while Daly recalls that "it was a challenge, he'd been doing everything the same way for a long time, and knew what each gallop was like. Then he had to really sit down and work everything out, it was all different."
Almost inevitably, Forster rose to the challenge, and Dublin Flyer's victory in the 1995 Mackeson (as the Murphy's was then known) and the Queen Mother Champion Chase won by Martha's Son just a few months ago are already on any fresh list the Captain may be preparing for his wall.
The latter success was a particularly fine achievement, as Martha's Son had had just one outing - he fell - since sustaining what many had assumed was a career-ending injury 18 months beforehand. Forster paid rich tribute to his horse afterwards, but there was an uncharacteristic quiver in what is normally the most rigid of upper lips.
Everyone who loves jumping horses has reason to be grateful to Tim Forster, for cherishing the belief that if you give a horse time, it will repay your patience twice over. Dublin Flyer has already won the first big chase of the winter campaign once. The second instalment could fall due this afternoon.