Sometimes the child you love most is the one who causes you the greatest grief, the one who tests your nerves, your patience and your wallet. Ask Colin Matthews which of BAA’s three London airports he would keep and he has no hesitation in selecting Heathrow, hassle and all.

Like all parents, the airports group’s chief executive would rather not sacrifice any of his family. But it’s easy to understand why Heathrow is his choice. It’s a hub, has more traffic than its siblings and, as Terminal Five’s more favourable reviews since the disastrous launch prove, it has the greatest potential for improvement.