Fixed it for you. When LHR can get over the impediment below they have a chance of they are willing to fund it. As you say they have been trying for 30 years without sucess. I doubt your assertions will change that fact.
"Except that £2.2bn-£18bn spent at Heathrow hasn't a chance of generating anything close £100bn of GDP growth, but is likely to redistribute GDP to the South East at the taxpayers expense."