I understand about the DfT having control over ordering rolling stock for provision of new - or effectively new - services; these alter the service levels of the franchise in a material way. I even understand why the DfT might have a strong view about stock replacement programmes, as these will significantly affect the financial outlay of the TOCs on access charges. However, I do wonder whether or why the DfT might get its underwear twisted about stock orders for strengthening existing services (actually, I know they do). Is this all written into the franchise agreements? Or is there really anything preventing increasing stock other than an unwillingness to do so?