One exceptional developer is making everyone else redundant
I have a developer who is genuinely exceptional. She solves in two hours what takes others two days. Everyone knows it, including her. The problem is the rest of the team has quietly stopped trying on hard problems. They wait. They route things to her. If she left tomorrow I think the team would collapse — not because the knowledge is locked in her head but because they have lost the habit of solving hard things themselves. I do not know whether to promote her, protect her, or do something I have not thought of yet.
Background
Professional services firm. The developer in question knows she is exceptional and is not the problem — she is generous with her time. The problem is the behaviour of the team around her.
Already tried
Asked her to document more (she does, nobody reads it). Tried pair programming (the pairs defer to her within five minutes). Raised it with her directly — she said she would pull back, it lasted a week.