The pilot reported he was on a cross-country flight with a passenger. On approach, he followed an airplane established on a left downwind for the runway. The pilot extended the airplane's downwind to allow space for the landing airplane to clear the runway. The pilot elected to use the paved runway instead of the 800-ft grass landing area adjacent to the paved runway because of the clearing airplane. He subsequently lost directional control during the landing and the airplane exited the paved surface. A "juggle" of the pilot's feet on the rudder pedals occurred during the excursion, which resulted in "over braking" and the airplane subsequently nosed over. The airplane sustained substantial fuselage and empennage damage. The pilot indicated that there were no mechanical malfunctions during the flight and his safety recommendation was, "Never underestimate a tailwheel airplane!"