if they're just connecting, does it matter where they do it? If you're giong from NY to Dubai and you don't actually want to get off in London, is there any special reason to use Heathrow?
Jourdain, I assume the purpose of HS2 is to get Londoners to consider moving their businesses north, rather than get northernish folk down to London. A bit of decentralisation would move some of the spotlight away from London, and no bad thing. But I appreciaate many would prefer an HS3 linking up cities in the middle of England.