> The benefit of talented engineers comes from the fact that they avoid costly pitfalls - not that they pump out more code per hour worked.

Not just avoid pitfalls, being able to put together a good architecture is a huge factor as well. The effect is cumulative. If you have a good design to begin with, everything becomes easier with less risk of bugs. The result is that implementing new, or changing existing functionality takes less time.

The 10x developer doesn't write 10x as much code, (s)he will probably write less code than the 1x developer.