If they want to talk about tankering on a BIG scale, they should take a close look at the amounts the airlines in the Middle East are hauling around.
The ME fuel prices are way below all other places. Emirates, Qatar Airways, Etihad, Oman Air, Gulf Air and Saudi Arabian Airlines.
How much extra fuel did Emirates carry on the A380 when they did 3 goarounds in Manchester and then diverted to LHR?