Last week Jacques Herzog and Rowan Moore kicked off discussions at Tate Modern about the role of architecture today. Herzog believes theory is long dead. Even Corb's writings are valueless, he told the huge crowd. The event was a sell-out, and latecomers had difficulty finding seats. Luckily, a distinguished-looking man helped them to their places - Tate supremo and Herzog client Nicholas Serota. Now that's a hands-on approach.