A plan that subdivides in a set of plans.
(=> (Branching-Plan ?Self) (And (Minimum-Slot-Cardinality ?Self Plan-Direct-Successor 2) (Exists (?A) (And (Represented-By ?Self ?A) (Fork-Node ?A))) (Exists (?B) (And (Method-Of ?Self ?B) (Planning-Stage ?B)))))