Letting a good developer "rocket ahead" optimizes for that developer (localized optimization) but not for the complete system (global optimization).
A more "global" optimization of that developer's time and energy, since they can do twice the work in half the time, is to mentor, support, teach, and otherwise spend their energy helping EVERYONE get to their level. Since they can and will get their "portion" of the work done quickly, they have bandwidth to add values in other ways as a force multiplier.
From my experience people like this end up in "lead" or "architect" roles.