This method returns an IInheritanceInfo which has a member called RelationsToHierarchyRoot which is a relationCollection dexcribing the relations from the root entity to the entity in hand or vice versa... (the sequence of JOINS used to construct this relation).
You can always traverse relation/s between 2 entities from either side of the relation to the other end.
This flag specifies which end to start with in building the relation.