ARLINGTON -- The "Horns down" was reserved Saturday for the Oklahoma fans at AT&T Stadium, ending a week when a controversy over the hand sign took on a life of its own.The Big 12 wrestled with whether or not "Horns down" would be an automatic penalty, finally deferring to the NCAA rule book that it would be a judgement call.Why not make it automatic, Big 12 commissioner Bob Bowlsby was asked before the conference title game."Because the rule is not written that way," Bowlsby said.