annie,

Of course it is possible for a sub to outgrow a Dominate. Just as it is possible for a student to surpass a teacher.

As for what to do if this happened in a full relationship, communication always helps. Getting the Dominate to see the need to learn is going to be a challenge, but should not be impossible. If the relationship is a good one, this growth will occur naturally and together. Maybe the reason this person has gone through so many subs is that he feels no need to grow, and thus never really can be in a relationship. Growth and learning are part of life.