The situation in the 7th at Hollywood today drove me nuts. Not sure what other things have happened. If this is allowed to go on, it is really easy to just manipulate the pools for your own good. For example, let\'s say you really like a 5-1 shot but you want to bet $10,000 and you think it will move the odds. well, one thing you can do is just put $50,000 on the horse to win, make the horse 1-9 for most of the betting. Not only will nobody else bet on your horse, but they will bet plenty on the other horses....then, as you watch the horses loading, you cancel $40k of your bet.....voila.....you got $10k down on your horse and you preserved your price. if this keeps up, it will kill win betting because nobody will feel confident about what prices they will get. Somebody cancelled a $30,000 bet at Hollywood with 2 minutes to go to post, so this is not far-fetched.