Excerpt from my latest Sasstrology post (please leave comments on the Sasstrology site):
"One of the mixed blessings of a composite chart is that it can repeat certain natal aspects of the partners. If those aspects are positive, it’s a clear bonus, because the energy is amplified in the relationship. But if those aspects are challenging, the couple can find themselves dealing with an intensified version of their own self-destructive habits or blind spots. If one or both have not dealt with their issues, these can become fault lines. On the plus side, this allows them to confront their issues, because the partnership makes it unavoidable."