I think the true 10x multiplier is not a technical skill at all. It is the ability to quickly cut through irrelevant tasks and actions to focus on the thing that will move the business goal forward fastest. It is enshrined in the concept of the MVP and the short iteration cycle. Quicky building something that does not solve a business problem is not productive. Work=force*displacement. No movement, no work.
A closely related skill is the ability to cut through all the abstractions and interfaces to get to the root cause of what is broken or needs changed. A technical and organizational debt buster if you will.
A closely related skill is the ability to cut through all the abstractions and interfaces to get to the root cause of what is broken or needs changed. A technical and organizational debt buster if you will.