Has Britain's budget watchdog become too all-powerful?

Officially the OBR monitors the UK government's spending plans and performance, and releases forecasts for the economy and public finances twice a year, (alongside the Budget and Spring Statement), which assess whether the government is likely to meet the rules it has set over tax and spending. At the time I reported that the then-Chancellor Kwasi Kwarteng had brushed away the offer from the OBR of an official forecast, which could either have given some comfort to the markets that the plan had been fully costed, or impeded the Truss administration's ability to announce those policy changes. At the end of October, one month before the Budget, the OBR is understood to have lowered its forecast for productivity - a measure of the output of the economy per hour worked - by 0.3 percentage points.