 The result of such back-test shows a drastic drop in performance after 1986, and even a flat performance from 1996 to 2009.However, a number of turtles (e.g., Jerry Parker of Chesapeake Capital, Liz Cheval of EMC, Paul Rabar of Rabar Market Research, Tom Shanks of Hawksbill Capital Management, Howard Seidler of Saxon Investment Corporation, Jim DiMaria of JPD Enterprises, Inc.) began and continued careers as successful commodity trading managers, using techniques similar, but not identical, to the Turtle System.Dennis managed pools of capital for others in the markets for a while, but withdrew from such management in the spring of 1988 after his clients suffered heavy losses.