Doug DeVos remembers sailing along "fat, dumb and happy" under spinnaker in 15 knots of wind on Lake Michigan in last year's Chicago Yacht Club Race to Mackinac when his 86-foot maxi Windquest suffered a knockdown punch.In a matter of minutes, the wind had grown to 40 knots, blowing the yacht on its side, with the boom in the water, until the spinnaker blew up and the crew was able to regain control.