In this article, the authors call for an end to an approach to teaching which makes a nonsense of pupils' learning of mathematics. They decry the over-regulation of instruction techniques based on Ofsted inspections, showing how much class time may be lost to prescribed events like warm-ups and lesson recaps. To illustrate their assertion, they present two different versions of the main part of a lesson--one taking into account the required class events evaluated in inspections, and the other ignoring them. (Contains 4 figures and 2 notes.)