Will she won’t she, will she won’t she, will she won’t she join the dance? Zara Phillips spent yesterday pondering her own version of the Lobster Quadrille as she wondered whether or not she – the glory, the darling, the star attraction of the Mitsubishi Horse Trials at Badminton – was going to spoil the whole thing. In the end, she decided to do just that. I don’t entirely blame her.

She has not only disappointed an awful lot of people, she has also annoyed a few as well. Bloody royal prima donna, who does she think she is? Just because we’ve had some nice weather she thinks she can do as she likes. She entered, let her finish the course for God’s sake.

Last year, William Fox-Pitt, one of Britain’s leading eventers, dropped out at the same stage, and he got roundly, even savagely criticised. I know, I was one of the savages myself.

The reason he dropped out was because he had done a poor dressage test and had lost all chance of winning. Huh, I believe I said. Does a football team save themselves for another day when they are 5-0 down at half-time?

But Phillips was by no means out of contention at the close of business last night, sixth in the standings after the dressage.

The question she then asked herself was whether or not the horse would be damaged by going round the cross-country course today.

It involved questions of equine welfare, sporting potential and commercial opportunity. That is not only the full list, it is also the proper order of priority – and there is no reason to believe that Phillips doesn’t adhere to it. This is not a moment for cheap cynicism.

No, it was all about the going. The bloody going. Of all the boring conversation horsey people have, the one about going is without doubt the most boring of all. I had a good old stump round the course yesterday, and I’d be damned if I’d gallop a horse of mine round there, even if they let me off jumping those frightful fences.

It was hard as the hob of hell, hasn’t rained within living memory, and if you gallop a horse too far and too hard on hard ground, you are going to get injuries. A horse weighs half a ton and all that weight, plus the momentum behind it, is carried by a single foreleg, which depends on a single tendon, at each jump, at each stride. Delicate things.

They’ve been doing what they can, dumping loads of topsoil about the place so it looks as if a megalomaniacal toddler has been building a toy motorway across the beauties of the park. More work and watering was planned overnight, concentrating on the take-off and landing areas.

But nobody knew what it’s going to be like this morning. For Phillips, it was a huge decision, and she took it early.

She has only one horse, Toytown, capable of competing at the very highest level. She has ten horses at her yard, all at various stages of development, but, for the next year or two, it’s Toytown or nobody for the top bananas.

And the horse has already lost a year with an injury, and that year was 2004, which was why Phillips missed the Olympic Games in Athens. It will not have escaped your notice that next year is 2008, and that the Olympic Games will take place in China. In fact, this year’s Badminton is an opportunity for Olympic qualification, but there ain’t no use in qualifying a lame horse.

So the question – to run or not to run – required consideration of the wellbeing of the horse, and also of the sporting ambitions of his rider. Then there is the third question. Phillips, being young, pretty, talented and, above all, royal – eleventh in line to the throne and no chance she’ll have to take on the bloody job, either – has commercial opportunities that are unique. I’m not the only person to have noticed that. Those who have invested in Zara want Zara to be seen: they want value for money.

Phillips gave all these things due thought, and then decided that this was not the week for a miracle. I have no doubt that she does so with great regret. It’s a great disappointment, and let’s hope she pays us back in China. All the same, I suspect it was the right decision. Three-day eventing – the really beautiful game – is revelling in Phillips, in her talent every bit as much as her family. Badminton is the better for her presence. But at the expense of the horse? The very top horse? At the expense of the Olympic Games all those months and miles away?

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