Charlie Appleby calls it "the Olympics" and few would challenge that claim. Royal Ascot has been too long enmeshed in the fabric of British culture to be anything other than a truly special occasion, but in the Platinum Jubilee year it has even greater allure, a higher purpose. Four of the top nine horses in the World's Best Racehorse Rankings, including the one who sits atop, will be here this week and several more that have yet to reveal themselves as members of that exclusive club. We will know them...