Boston: the discomfort zone? -- Globe profile of Tiffany Dufu, a bright young professional who recently moved from Seattle to Boston with her husband, who's getting his MBA from MIT. Sounds like a typical post-grad couple in this town -- except that they're black, and she has some reservations about starting a family here, where racial animus, class consciousness, and good old provincialism lurk just under the cobblestones. Or do they? Yes, sometimes they do. The lack of diversity in this town (not including transient college and grad students) is something I think about quite a bit, and it frustrates me no end that I really have no solution, except that Tiffany and a thousand more families like hers need to stay here, move into the burbs, send their kids to public school, etc. for any change to take place. Tall order.