The person who makes sure there are no such minefields makes a lot less great advances him/herself - they're busy working in a careful, orderly and considerate manner. And then the other engineers perform close to his/her level. That's not the 10x engineer.

However, the person who lays the minefield may only be a 1x person talent-wise, but since he puts his colleagues on 0.1x, s/he is effectively the 10x engineer of that team.