But she was good at setting a vision, expressing that vision, and making sure it was being followed and getting her direct reports to move things in the direction she wanted.

As far as brilliant, I'm referring to raw intelligence. You could tell her new information and she would instantly digest it and apply that to new areas. Also, if you were in a meeting with her once, she'd remember you and what you talked about. If you mentioned that you had kids for example, the next time she saw you months later she'd ask how your kids are, for example.