Sincerity. Dominance. Small difference :)>
"... As they move in, the antagonist rotates their wrist 45 degrees to put you in a subordinate position..."
"... simply add your left hand to the fray, placing it on theirs in a sincere gesture, but applying downward pressure..."
"... Once in a Double Clasp, the only way out is to grab your opponent's right arm. There are three stages of dominant grab - forearm, elbow and shoulder..."
(Source: Wired, February 2010 issue)