Schools rush in where angels fear to tread. Although some of the area's larger, more timid theaters are scared to death of Stephen Sondheim, our local universities know a nifty composer when they hear one. So what fun it was this spring when, quite by happenstance, Lindenwood, Wash. U. and Webster gave new definition to the notion of Side by Side by Sondheim. All three schools staged Into the Woods, and all three shows were a happy reminder that university theater often provides one of the best deals in town. Anyone up for Merrily We Roll Along?