I was surprised, and pleased, to come across the following video on www.ted.com where Bill Gates urges people to hold politicians to account for the budgets they approve.
In the video he makes a good point about the level of expert external scrutiny applied to the financial position of publicly-listed corporations. There is very little of this, he says, applied to public sector organizations such as the State of California.
Bringing this back to the UK for a moment, the government's proposals for armchair auditors might improve the level of scrutiny at a transactional level. But, knowing what every £500 has already been spent on is not the same as holding politicians to account for the big picture: the sustainability, or otherwise, of the public services that they want or expect to receive.