It's kind of a catch-22, because a lot of these horses would never have been conceived or born without the impetus of racing itself - but the racing spoils so many of them, or at least weakens their legs for later in life. Sort of like the college or pro football player whose injuries start catching up with him in his 30s and 40s . . .
Man O' War didn't run in the Kentucky Derby because his owner, Sam Riddle, didn't believe in allowing three year olds to run that distance so early in the season. But he was fabulously wealthy and could afford to do exactly what he wanted with his horses.
Those of us who buy hunter/jumper prospects from the track or the racing farm are most concerned about the state of the horses' legs, particularly if they've seen a lot of racing. It's usually better to buy one that washed out in training - less likely to break down.
Do you just adore The Dog Whisperer, Cesar Millan, like I do? I bet I watch his show 5 times a week ... he's a marvel and simply amazing.