Atlanta’s new Cobb Energy Performing Arts Centre is opening. “Yes, the play, or the opera, is the thing. But the performance hall plays a role, too, and not just in the critical functions of acoustics and sight lines. Its architecture and interior design set the stage, so to speak, for the experience, visually and psychologically. Unfortunately, the execution goes awry. A building with ‘arts’ in its title (below) should do better than knockoffs.”