I did not want this to clog up the Metro thread.
I know about the capacity constraints. I know about the lack of paths on the northern line. I know there is a Metro planned, but it still seems possible that a new branch from the Northern Line across the green fields and elevated into the airport can be done. It would be relatively painless no?
Even if the services were from the new Docklands station to the airport surely it could cut into some the DART paths while serving stations along the way. Not to replace the Metro, but to eventually integrate with it at the airport? I 100% agree it is not the ideal solution.
Just explain to me why it would be a very bad idea.