I appreciate the response.
I suppose I must not be understanding something. If we were concerned about which specific horses were the closest, it would make sense to keep all values in the list, even repeating ones, but from a performance perspective, it's unecessary to compare the same scores multiple times, so using a set that only stores unique numbers makes sense for speed, as we are only concerned with the spread, which would be unique. Also, I don't understand what is meant by "all horses tie". If all items in the set are unique, comparing N to anything other than itself, i.e. N+1, could never tie. Sorry, not trying to be thick, just could use a more detailed explaination why it thinks they are a tie, and how not removing duplicates would be more efficient. Thanks for any feedback!