Originally Posted by
4Greens
Twin engined aircraft are much cheaper to operate and have the same or better range than four engine models.
True. But that only matters if it's aircraft-mile costs (as opposed to SMCs) that are important and/or if you want to fly a long way. Which, admittedly, is the case for many (but not all) markets.
If there were no routes on which the A380/B748 had better economics, everyone would just have bought 777-300ERs instead.