To me, there are two main factors in determining that a bias is useful. First, is it at least based in some kind of fact? Anyone can come up with a theory and support it dogmatically, but no matter how hard I may try to convince you that the moon is made of cheese, you can always just tell me to take a bite of moon-rock and prove me wrong.
It’s cliché, I know, but horses are not just lines on a piece of paper or numbers on a saddle cloth. Horses are living, breathing animals that have their own personalities and tendencies, and sometimes replays can provide an angle that all the number-crunching in the world can’t. As Warner Wolf would say, “let’s go to the videotape!”
To me, betting the Breeders’ Cup is like anticipating the final chapter of a really good book before the author has written it. You’ve had a feeling how the book would end all year and now you get a chance to find out. Sometimes the ending isn’t exactly how you picture it. Many good books, maybe even the best books, have twists. If you can see one of those coming, you might just win the BCBC.