Leave it to the experts?
That's exactly what I am doing.
What does it tell you when the Spanish flag carrier, Ibera doesn't fly Malaga-JFK
Or when the UK flag carrier doesn't even fly Edinburgh-JFK (they tried it with a 757 and failed).
May I suggest that the brain trusts at DAL learn something from experts, The fleet planning experts at their respective nations carrier seem to feel differently, then DAL's.
I am going with the home team on this one.
The main arguement I see against your rant is that DAL has the ability to connect many many more pax for these flights. Where as the foreign carriers you mention don´t have as varied a route structure here in the states or in their home country for that matter.
Just because the city pairs might not make sense think about all the connection possibilities......RIC-JFK-Edinburgh or ATL-JFK-Malaga just to name a couple!