But the article does say that Airbus and Boeing each had a major project in recent years (A380 and 787) and they're unlikely to have anything major for the next decade. A350 sounds pretty major to me.
The A380 and B787 introductions were very rocky, with delays added to delays added to delays. On the other hand so far the testing of the A350 as been incredibly smooth.
I know that it's too early to draw any conclusion, and that the A350 is still one year from EIS. But when you take into account the actual competence of making a new plane, and how quickly it can be lost, I wouldn't be surprised if the lesson learned is that it is more economical for Airbus and Boeing to release new planes more often...
But once it was settled the engineering went smoothly. Or, should I say, has been going smoothly so far.
The skills involved in designing a plane are vastly different from that of figuring out which plane your customers will want 5 to 30 years from now.