18+

I'm watching the Chilean rescue intermittently. There's only so much joy and happiness a man can stand at once. Last I saw, they had recovered 18 of the men. That's over half-way there. No glitches, no delays, no goofs. Bravo for human ingenuity, sheer dogged persistence, and good, solid engineering.

The whole mood, from the BBC reporters to the people back home, and the cheering crowds on the streets of Santiago, is overwhelmingly positive and joyful. This is going to have an immense and beneficial effect on the approval ratings of the politicians involved, on the Chilean national self-image, and even on Chile's reputation and trade with the rest of the world. After all, having seen the professional and competent way this whole operation has been organised, who would not trust a Chilean company to deliver the goods?

It's a triumph, and it's all down to one decision. I don't know who decided it, but it was a masterstroke to say at the outset that the men may be down there until Christmas. Everyone who heard it groaned and sent up a silent prayer for the poor buggers trapped underground. And now the operation is under way in October, and may be finished tonight, we are in awe of their professionalism and progress. Tim Wilcox of the BBC is almost wetting himself with excitement at the 'remarkable' rate of recovery of the men.

Imagine that, when contact was first made with the men after 17 days, the Chilean authorities had said that they expected the men to be home with their families in a couple of weeks. The whole world would be wondering why it was taking so long, what incompetence had led to the delays, why didn't they let some real engineers take it over, and so on.

I would bet serious money that the engineers had a pretty shrewd idea from the start how long it would take. Drilling through rock is what they do, after all. It's a classic example of the fundamental customer service principle: under-promise and over-deliver. If you think you can solve a problem in twenty minutes, tell the customer you will call them back in half an hour, and then try to do it in ten. It's called 'managing expectations', and I think the Chileans have done it brilliantly.