Lobbies have hijacked the aviation consultation, and it's a shame that prevents Britain to enter the 21st century when it comes to air travel.
Here are my comments to the Economist article:
Short sighted indeed... You forgot some other important considerations.
1. External costs.
LHR is in the worst place possible -a marshland that requires to fly over 2m people and space constrained.
All other capitals have consolidated and moved their hub airports, but for London no one's talking about CLOSING any.
No one is either seriously planning to offload shorthaul flights with HS2, even though Eurostar has 70% of passenger share between London and Paris.
In a nutshell: a botched consultation that's been hijacked by lobbies -in particular those using and owning Heathrow.