On Radio 4’s A Point of View, John Gray discussed Barbara Tuchman who defined folly as pursuit of policy which is demonstrably counterproductive. Quoting from the BBC article: a policy can be identified as folly if it meets three tests. It must have been perceived as counterproductive at the time and not just by hindsight; a feasible alternative must have been available; and the policy must be that of a group and persist over a span of time, not the act of an individual ruler. Spot on with regard to traffic control. As we know from Kenneth Todd, as far back as the 1920s, traffic lights were deemed undesirable. “Roger L. Morrison, Professor of Highway Engineering at the University of Michigan, listed their drawbacks in 1929: delay to traffic; speeding up to beat a green light; running red lights; making detours to avoid lights; contempt for unnecessary traffic regulations; rear-end collisions; helping criminals rob their victims (see Morrison, 1931).” On 5 October 1929, the Washington Herald quoted testimony from renowned traffic expert, William Phelps Eno, before a Senate subcommittee, which included his condemnation of automated traffic signals as “the greatest detriment to the regulation of traffic yet invented”. Eno, Blackmore and the AA all advocated offside priority. Feasible alternative? Equality Streets/filter in turn.