dash6
If you call it "Heathrow East" most customers won't notice the difference.
Oh yes they would! Once they discover that their (say) less than 1hr to the airport is now 2hrs.
Example, I've lived in West Hertfordshire and North London for 30 years. Going to the Isle of Man was a doddle from LTN. Now I have to schlep to LGW because I have no choice.
I return to LHR on Monday morning and am very glad that it's not to a 2nd at LGW or an island even further away.
Also, to repeat myself from other threads, Britain is broke and the cost for a new airport does not exist. Forget that it would be 'paid for by commercial companies' the UK would have to put an inordinate amount of govt, local govt time and money and effort into legislation and approving new infrastructure. It would have to be squeezed into spaces already tight. Consider the enormous problems of Cross-Rail construction for an example.