BDL, I'd suggest a perusal of an article in March 2008 National Geographic which differs from what you claim. Living with a McNab border collie, myself, I can vouch for the veracity of the bit about bcs, for sure!:-)
I was talking to a friend who watched the race and is very knowledgeable about horses. She says the people who come out once a year to bitch about races should concentrate more of their efforts in going after glue factories, etc.
Also, she said there is a general agreement that two year old's bones are not strong enough for racing AND they are developing some synthetic racecourse material which would be easier on the horses legs, feet, bones, etc.