A double fan consists of two unseparated plant divisions. A single fan is one plant division. The main stalk lateral branches that hold the flowers. A dormant cultivar is one whose foliage dies back below ground level in the winter so that no green is visible.
Evergreen varieties have foliage that stays green all winter.
The does not mean that it retains its summer appearance. We understand evergreen in a Holly. In cold climates the foliage will be frozen and limp. In warm climates, the foliage will look much as it does in summer. They do not show any active growth over the winter even in warm climates.