A tune evidently close to the heart of Eye favourite Stephen 'Gone-native' Hammond, as evidenced by this written answer given on the 26th November:
Kate Hoey: To ask the Secretary of State for Transport pursuant to the answer of 4 November 2013, Official Report, column 45W, on railways: south west, for what reasons lease costs for rolling stock are considered to be commercially sensitive.
Stephen Hammond: The leasing costs for rolling stock are the result of negotiations between two private sector commercial entities, the train operating company and the rolling stock leasing company. Putting such information in the public sphere would give advantage to each party's competitors and hinder future negotiations between such commercial entities throughout the industry.
Hmm... Advantage and Hinder?
Surely the name of an act in this year's DfT Christmas panto?
No matter!
Of course the real hindrance 'to future negotiations' on allocation of scarce trains is done by DfT's random-rolling-stock-cascade-generator, which inhibits the effective operation of the entire train leasing market.
A point made transparently clear from section 25 on page 9 of the summary section of the Competition Commission's 2007 'Rolling Stock Leasing market investigation'.
Go figure!