Two different story lines have emerged midway through the Big Ten’s inaugural season of divisional play.  The Legends Division is locked in a logjam at the top, as Michigan State, Nebraska and Michigan are tied with identical 3-1 conference records.  But one school has emerged from the pack in the Leaders Division. Surprisingly, it’s not preseason favorite Wisconsin.  Penn State is the last team unbeaten in Big Ten play at 5-0 in the conference. The Nittany Lions have a bye this week before a three-game gauntlet to close the regular season begins Nov. 12 against Nebraska.  Road games also loom at Ohio State and Wisconsin.  Penn State might have trouble scoring points, but Purdue coach Danny Hope says coach Joe Paterno has one of the nation’s best defenses.