I think you will find a 2 seater motor glider more efficient, and by your argument-
gasp.... The A330-------- less of a fuel burn than the 777
.... but they both can't fly DXB-JFK.
For the sake of the case, stay focused and compare apples with apples.
Take a 201 and a 203, on the same day, with both full pax load, see what you burn per pax and per kg, check how much extra cargo (in % and in t) you can load, and then come back.
A 330 (especially the -300) is as fantastic aircraft on its specific routes, no doubt.
If you dig a little deeper, you would realise that any twin with only two landing gear struts is a fine machine, as the manufacturers match each other quite nicely.
It is the anachronistic design of four engines and four struts that make the whale too heavy to be able to match the efficiency of twins. As simple as that.
The A380 is quieter, bigger, makes more money due to the hype as long as you fill it, it has a beautiful bar and so forth. I do not deny it, it has its attraction and assets. But neither can any 380-fanatic deny that it is simply too heavy (for the time being) and any quarter pounded self proclaimed professional of the skies might remember lesson number one of aerodynamics: The heavier, the more burn.
The T7 dates back to the early eighties, it simply can't be as sophisticated as a brand new model. The mere fact that it still competes in efficiency with the A380, should point out the latters weakness: It is simply not as efficient as proclaimed.
This is what is bugging me. An aircraft that brings only fractional improvement, that has a very narrowly peaked best performance curve and is ordered in huge numbers, is a potential threat to a company.