AA were selling well from Newcastle before they pulled the flights, and pulling in passengers very nicely.
I also dont believe we would be having this debate if CO had started first on the route but AA got onto the route first. As they could start the route 8 months before CO had been in discussions to start the route. If CO had been first on the route then I think we would have had a very successful NY route operating for the last few years.
Finally the Britsol example is totally different and should not be used to draw an conclusions as to how a Newcastle service would work.