[QUOTE=Elles;8131410]
Well, I am wondering how the change in the courses changed the breeding. Certain families / lines should be declining and certain bloodlines should be getting more to the foreground.[/QUOTE]
It may have happened, you are right. But, although I may have interchanged both words many times in my posts, both sport and breeding have evolved and not changed. As for the sport, caracteristics have not dramaticaly changed, the difficulties became more difficult, and more importance was put on some issues and less on other. It remained the same sport. This reflects in breeding in a way that new abilities did not necessarly have to be added in the horses. The existing abilities add to be improved. I have difficulty to put my thought in english on that but I hope people understands me, or at least one did and can put it in clearer words!
As an example, an old type WB horse may becaume, over generations, more supple, improve its balance, become more reactive etc with selective breeding. This happens on a relatively long period of time. You do not change the horse, you select certain traits, and improve them. If, for example, I started a reining horse breeding program with Hanoverian mares. I would have to bring in the mix abilities that are not present in the horse. The balance is totaly different. The cattle instinct is innexistant. The ability to stop on a dime and spin are not their at all. I would have to change completely my horse.
So this being said (probably not in the clearest way), I think that a good sport horse line has what it takes. If carefully bred over the generations, by a concientious breeder who understand the sport, but also understand its lines, will continously evolve with the sport as it will keep its strenght, and improve its weakness.