Manchester connects to MORE major cities in the UK than anyother airport including Glasgow; FACT
Can we leave the willy waving to the respective airport threads? The question is - could a new island airport offer useful domestic feeder routes that LHR can't.
The answer is - given the likely PSC, which Silver repeatedly refuses to quote, and the space constraints that an island airport would face, clearly not.
Now about those slots - good point, their value would indeed vanish with a new runway at LHR. But BA would still face huge costs if forced to move to the new airport - more so than any other airline.