If you live in Britain, and haven't spent the last six months hiding under a rock, you'll have noticed the noisy, ongoing and definitely not tedious debate about which of London's major airports should get a multi-billion pound expansion.
In the red corner is Heathrow, which claims to be Britain's hub airport, and consequently that the best way of using scarce public money is to make it a bigger hub. In the blue corner is Gatwick, which claims, in not so many words, that two hubs are better than one.
Two weeks ago the Davies Commission on airport capacity backed the former. But this whole debate, data analyst Tom Forth argued on these pages recently, is entirely irrelevant to large chunks of the country. Look at the figures, in fact, and the UK's hub airport isn't Heathrow at all; it isn't even in the UK. More passengers from regional airports fly via Amsterdam Schiphol than via any of London's airports.
The results of Tom's analysis were so striking, and so counter to the prevailing wisdom, that he was invited onto BBC Radio 4's You & Yours programme to talk about them. You can listen to the clip here:
As a special bonus, if you're really getting into the whole listening-to-CityMetric-writers-talk-about-air-capacity thing, you can listen to editor Jonn Elledge talk about the subject on the New Statesman podcast here. The relevant section starts about 20 minutes in, just to the left of the "Stop Heathrow Expansion" badge in the centre right of the player.