Originally Posted by Riot

The "2-year-old" conflict, specifically, however, seems to stem from those that do have experience training 2-year-old horses (in any sport - cutting, reining, racing, jumping, etc); and those that do not.

There are many published studies regarding development of the immature athlete (try google) - it's not rocket science, nor all that new. Bone remodels appropriately to needed stress/strain in a positive way; cardiovascular and pulmonary changes must occur; metabolically enzyme systems adapt to streamline physiology based upon requirements ...

The most dangerous thing you could do, for a potential racehorse that you wanted to run at 3-4-5 years of age, would be NOT to run it at 2-3 years of age. Those are the horses that never develop the physical characteristics that make them athletes, as their bodies are never asked to develop what it takes.

"Good" horsemen bring animals along at their own rate, in a positive way, as their physical and mental abilities mature into increased athleticism. Bad horsemen don't. Watch every year as the new 2-year-olds come out, see how they are trained, where they are placed, etc.

I can't see painting all 2-year-old racing with the broad brush of "bad". It hasn't proven out. In fact, it's been proven opposite - a good, appropriate athletic foundation is the best insurance for a longer, healthier career.