Something bothers me about a twin jet
delta wing. Concorde type wings don't have great lift on take-off hence higher necessary speed. Look how Air France's poor last flight struggled valiantly on 50% power...with afterburners!
Now this new Boeing will have an awful lot of fuel + ~200+ people weight for a 9000 mile dash, and no afterburner take off. Even with high-bypass power, how close to the edge will -it- be with one engine out on take-off from Paris to Hong Kong?
My only guess is that the twin engine layout is a ruse to Airbus in case they want to compete. I suspect that, along with the canards, this element of the `concept car' will never see the outside of the `motor show'.