Hospitals that permit concurrent surgeries consider it an efficient way to deploy the talents of their most in-demand specialists while reducing wasted operating room time. For patients, however, it can come as an unsettling surprise — especially when things go wrong. In a battle pitting a star surgeon against a great hospital, Massachusetts General, the question is: Is it right or safe for surgeons to run two operations at once? Is it right that their patients may have no idea? The conflict went on for years. And it isn't over yet. [Registration required.]