It was no exodus, of course, but when Kathleen Triem quit her job at a Manhattan design firm in July 1996, her associates were thunderstruck. Triem had decided to practice architecture in the more leisurely atmosphere of upstate New York and, as her colleagues saw it, she was shooting herself in the foot. One man went so far as to say that she’d be back in TriBeCa before you could say “Poughkeepsie.”