I watched their every move - through all three telling, testing and beautiful disciplines. The balletic beauty of the dressage on Day One - the beautiful strength of magnificent horses, controlled by some of the best riders in the world, combining to give a performance with the grace and power of a Nureyev. Side-steps, trots, shifts and subtle turns - controlled by a delicate pull of a rein, a squeeze of the knees, even the downward pressure of a bottom. It even rained and yet they came through with honours in tact - on course for a medal. It was all done in the splendour of the grounds of Greenwich Palace, the Naval College, Queen's House and the Observatory.
Day Two's cross-country is beatific brutality - not cruel, never that. But the brutal challenge of a maximum test: the course sweeps across Greenwich Park - gallops, canters, subtle 'pops' across easier jumps; the skill of a rally-driver required for some of the more testing combinations. Water. Colour. Odd shapes. Steep, slippery slopes, and, all of the time, as in the dressage, a crowd baying for glory. A nice fillip but it must run the risk of distraction.
Not for these five. They had a job to do and, at the end of Day Two, were doing it fantastically well - still poised for 'metal'. Maybe even Silver or, hold your breath, Gold.
Day Three took them back to the manicured sands in front of the Palace. A capacity crowd, knowing their horses and their sport and that Team GB was in with a chance. Germany, New Zealand, the Swedes - a host of nations with troubling track records of success in their pedigrees. The Germans boasting Michael Jung, probably one of the best eventers who has ever saddled a horse.
But in Mary, Tina, Nicola, Zara and William we felt, just felt, we might have their and his match.
They rode their hearts out over jumps that would put the fear of God into weekend-riders and parents, like us, with children who adore their show-jumping.
Singles, doubles, spreads and the water. A twisting, turning test of riding, of agility, of precision, of pace.You have to 'go clear' - nothing knocked down - and you have to do it within a set-time.
So much to ask and so little time to do it in, just 83 seconds.
I won't go into the final detail - it didn't go perfectly. Bu there was none of that 'we gave it our best shot' nonsense, although they did. They admitted the Germans out-performed them on the day. That is honest but it is also noble.
Silver, say the Americans, is for the best losers. Hope they are happy with that philosophy.
To me Silver went to a team of five wonderful individuals, combining to be so much more than the perceived sums of the parts. Mutual support and mutual respect. Two were in with a real chance of individual honours. But, again, no.
Silver for the team, a just a sense of pride in a job well done for all five individuals.
Today they joined me in the Olympic Park studio for the Lunchtime News.
I glowed with pride. I am a self-confessed fan and admirer - of the sport of of its brave and clever practitioners.
A monarch's grand-daughter; a woman who, just a few years ago, broke her neck; a lone man among five women - a towering 6' 4" who once took time out to talk to my son about his show-jumping ambitions; the daughter of a national hunt trainer and the new kid on the block. They all played their parts and made me very proud. I hope we can all share in their achievement but, more importantly, admire their comradeship, self-effacing skill and ability to remain the lovely people they began as - just four short days ago. A lesson to us all.