Can a horse's going preferences evolve over time? Can trainers help with this?

And why do trainers from time to time let their horses ride on previously unsuitable ground types? It's like today at 2-55 Sedgefield, a horse called Bill And Barn. All its achievements were on soft and heavy ground, beginning with early PTPs and up to the last race in October. Good ground was a negative and even a reason for declaring the horse a non-runner a few years ago (by P. Nicholls). If it's running today, does it mean that the new trainer expects some real changes regarding ground as a result of training? Or is it just a happy-go-lucky attitude?

A horse's going preferences can sometimes suddenly change if there is an application of cash

Not a trainer, just a punter, and not an especially good one but...

Going preferences can come from different causes, some of which can change with time. For instance:-

Strength (or lack of) to repeatedly pull hooves off, or jump out of, sticky ground. Of course, strength can change through training or just age.

Leg or shoulder injuries mean hard impact on fast ground might be painful.

Wind (breathing) problems.

And then some horses' chances depend on what the going does to others. For instance, a slow old plodder might need the mud not because he likes it himself but because it slows down his rivals so he is still in contention at the last. Ah, but if pace is the problem, perhaps a small field or tight track will stop them going too fast.

And just as not all soft going is alike (eg wet mud or sticky, drying ground) so nor is all fast ground which can be bare, dusty earth or covered with thick grass which will take any sting out of the ground.

So yes, some preferences can change; some can depend on the rest of the field.

More in the flat-racing hemisphere, some colts and fillies learn to handle any ground as they mature.

Thanks for your replies. All this probably more relates to horses gradually adapting to softer ground, as they become stronger. Can a horse learn to handle faster ground which it didn't like before? Does this require a different leg/hoof movement? Some commentators, while watching a horse going down, can say whether it will like a particular ground based on its movement pattern.

Horses' action: broadly speaking, high knee action favours soft, low (so-called "daisy-cutting") action favours fast ground.

Can a horse learn to handle faster ground which it didn't like before?

Yes, Teenoso was one.
https://en.wikipedia.org/wiki/Teenoso

When I owned a filly, she hacked up under top weight on officially hard ground at Bath as a 3yo. But next morning there was heat in her nr fore, and when I got her home and had her scanned, there both her front tendons were torn.

It took two winters of turning her out in deep mud to get the tendons to refill with collagen, and for the fibres in the collagen to align vertically, to provide some support (the idea is that the effort of pulling the legs out of the mud day after day causes the tendons to heal with the fibres aligned vertically). Even then, she was never going to be as good as new, because tendons never heal with the fibres crimped as they are naturally, which allows them to act like a spring on hard ground.

So, when she reappeared as a 6yo, there was no question of running her on firm ground, even though she acted on it according to the Form Book. In the end I got a seller out of her on the old Fibresand at Wolverhampton - not the usual surface for horses whose best run had been on hard at Bath.

Conformation can be another factor.

James Willoughby points to running style as another factor, which is to an extent under trainer control.

In the Racing Post's Big Jump Off supplement in today's (Monday's) Racing Post (hurry while stocks last, though iirc it will also be published separately and is of course available online to members), Willo writes:-

Horses trained by Mark Johnston, for example, are more effective on fast ground, probably because of their shared style of running.

URL for Willo:-
https://www.racingpost.com/news/members/the-big-jump-off/what-machines-can-tell-us-about-how-jump-racing-works/515126

I visited Nicky Henderson’s yesterday and he has a “Wexford Sand” gallop that is very deep 6-8 inches and teaches horses to lift their feet correctly when they run on softer going.

Our horse didn’t go on very soft ground last season but won twice on good. She was flying around this gallop without any issues so we will see if it works when she encounters deep ground later this season.

Hibore, that's interesting. I wouldn't have thought you could change a horses running technique but then i guess that is what dressage is all about. Let the forum know if it works, good luck.

Will do swifty, She’ll be running on good ground where possible to start with around end of month. But Dec and Jan we will need her to go on some level of soft.

I’ll update the “buying into a horse thread” when I know more.

They said Night Nurse wouldn't go on the ground at Cheltenham for its second CH.
So it started 13/2.

They should have told the horse.

I think there must be more money lost backing the state of the ground to suit the horse, than simply backing it on its form.

That's exciting how trainers can do different tricks to help the horse with adaptation to various ground types. Though not all trainers do this, I think. A lot of things really depend on conformation and, consequently, on running style/knee action, but if this can be changed by drills like Wexford Sand, at least to some extent, that's good news.

Two crillons ran at Galway in very heavy last weekend , neither performed well.