There are already non-state-of-the-art facilities (and some fake, won\'t really do anything facilities) in Kentucky and other states. Why do you think a good portion of the US Olympic team trains in Denver? Sure, training at altitude gives one a boost.
Edit: But let me add, I doubt that was any significant facter in the Derby success. That effect only lasts a week, 10-15 days or so. More important parts of MTB success at the Derby, IMO, was that:
1) he was well-trained for distance
2) he\'s a small, agile, light horse that can skip over the mud better than bigger, heavier horses
3) once he was bumped at the start and squeezed well back, he had a 6 1/2 -furlong canter with no mud in his face until he had to sprint past tiring leaders.
4) Borel put him on the inside part of the 1-path, where no hooves had previously tread, very firm area of the track