CASS SUNSTEIN UPDATE: Powerful Shaper of U.S. Rules Quits, With Critics in Wake. ” Cass R. Sunstein, who wielded enormous power as the White House overseer of federal regulation, came to Washington to test his theories of human behavior and economic efficiency in the laboratory of the federal government. Now he is departing with a record that left many business interests disappointed and environmental, health and consumer advocates even more unhappy.” He’s a nice guy, and a smart one, but going in I don’t think he fully appreciated the messiness of how government actually works. I’ll be interested to see how his experiences inform his subsequent scholarship.