If you thought the Derby Point System was poorly devised...

[lemoncrush]

I'm not surprised by their reaction. There's nothing in the official rules that says you can't do this. Taking the same horse multiple time was an oversight when they threw this game together, and it's too late for them to change the rules now.
Props to the guy that figured out how to beat the system. If this game cost money to play, a lot of people would be pissed, but for a free contest, I guess