U.S. men use different techniques in latest Boston Marathon shutout

"Hall is the defending Olympic trials champion and finished the Boston Marathon in 2:08:41, while Keflezighi was the 2009 New York City Marathon champ and finished Boston in 2:09:26.

Keflezighi paces himself by the strength of the field....Hall, on the other hand, paces himself with his stopwatch...Neither technique has proved supreme."