The shooting deaths of three biology professors at the University of Alabama at Huntsville this month, allegedly by a colleague who had recently lost an appeal of her tenure denial, seemed to many observers to confirm the worst about faculty workplaces. In conversations on The Chronicleâ??s Web site and elsewhere, people have seized on the killings as evidence that academic life today is a petri dish for madness: The high stress of the tenure process, the pressures to be brilliant at research and teaching, the cloistered environment, the extent to which internal politics affect peopleâ??s careersâ??itâ??s a combination that could damage even psychologically healthy people.