Running the NHS is like steering a supertanker. It responds with majestic inertia to a whirl on the wheel, but before you know where you are, you are ten miles out to sea.

Given a simple objective, the service seldom fails. But it can easily overcompensate. Two years ago the order went out to balance the books and save Patricia Hewitt’s job as Health Secretary.

The books have been duly balanced, though Ms Hewitt was still cast to the sharks. But, having eliminated the deficits, the NHS is now heading for an embarrassingly large surplus of almost £1.8 billion this financial year.

Under Treasury rules all of this money stays with the NHS. But that is small compensation for the hundreds of patients denied access to modern drugs this year because the NHS said that it couldn’t afford them. It also makes the promise by Andrew Lansley, the Shadow Health Secretary, to spend still more on the NHS look even more ill-timed.

Where will the money be spent? The Department of Health would like us to believe that it will be invested in new and innovative services. (The art of making spending sound virtuous is to call it investment.)

In practice, all that will happen is that the NHS will relax its controls. The cost savings were made in 2006-07 by squeezing emergency care, reducing the prices paid to hospitals for such care and cutting staff by 8,500 – the first fall in numbers for ten years.

Staff numbers only have to begin creeping up again and the surplus will disappear.

Cost-of-living salary increases have also been under tight control, which cannot last for ever.

And the whopping surpluses made by the strategic health authorities have come in part from raiding their training budgets. That is another short-term economy that cannot realistically be extended indefinitely.

So, the impression that the NHS has suddenly become much more efficient is, alas, an illusion. It has jammed on the brakes, squeezed its staff and denied some patients the care they would take for granted in other countries.

As a result, it is in surplus. But it won’t last.

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