It really takes one accident that can, even partially, be traced back to problems with the carbon-fibre construction, and suddenly the promised 20% fuel cost sa

It really takes one accident that can, even partially, be traced back to problems with the carbon-fibre construction, and suddenly the promised 20% fuel cost savings will seem miniscule when compared to the horde of fleeing customers. Composite fuselage would be a good thing per se but it's one of the technological advances that you can only build slowly, with lots of testing and enough wrecked planes, until it matures into "proven technology". Now it seems that so far they've just patched problems with the construction as they appear.