Yes your right although I'd give more credit to the trainer influencing the odds than the jockey. The jockey can win or lose it for you once the race has started, but the trainer can win or lose it before the horse even gets to the track. It's really about putting the right horse in the right race. A colleague of mine has a share of a smart 3yo filly that stormed home to win by 5 or 6 lengths at Flemington on Cup Day. That filly was nominated for two or three races before finding the right one. You could probably have put any of a dozen riders on her for the same result. When you see a late riding change you generally don't see a corresponding change in the odds.

My question was largely rhetorical but all things being equal I'd put my money on the rider who has shown the advantage (Rider B) over the one who's only met expectation (Rider A).

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Pixie

"It's worth remembering that profit isn't profit until it's spent off the racecourse." -- Crash