If you want to get a British entrepreneur worked up, one topic is bound to raise their temperature to boiling point: the behaviour of the clearing banks.

To ordinary business owners, it appears as if these organisations are the institutional equivalent of Jekyll and Hyde. In the space of a year they have gone from being rampaging expansionists to capital-starved risk-avoiders. Everyone in business is being battered by the blowback from the credit crunch. What on earth is going on in the financial services industry?