From ISAF appendix A
A2 SERIES SCORING
Current Position
A2.2 Series Ties
(b) If there is a tie in series scores between two or more boats, each boat's race scores shall be listed in the order of best to worst. At the point where there is a difference, the tie shall be broken in favour of the boat with the best score. If a tie remains is shall be broken in favour of the boat that obtained her best score nearest the end of the series. If a tie still remains it shall stand for the series results, and boats tied for a prize shall share it or be given equal prizes.
if this is true it would take a first for USA in race 11, in order to win a tie on points.
It's gonna be hard to shake off AUT. Good luck to Team USA on their pseudo match race for the Gold... Congrats on locking up the silver.
Mike