John Kao, a Princeton- educated mathematics Ph.D., took workplace diversity seriously. He was the type who not only raised the issue of a lack of diversity with his employer, the University of San Francisco, he submitted a written complaint alleging racial discrimination and harassment. A 485-page complaint. Fifteen months later, in August 2007, he generated a 41-page addendum. His employer responded in two pages. Not surprisingly, Kao wasn’t satisfied. A tenured professor, he met on Jan. 3, 2008, with a …