While CWE-1000 has mutual exclusivity as a goal, it has been difficult to accomplish. It tries to reduce overlap as much as possible. The explicit modeling of chains and composites has simplified this problem somewhat. However, there are still multiple perspectives embedded within the hierarchy, and not all chains or composites have been detected.
Models Inter-Relationships
The explicit modeling of relationships (besides parent/child) seems to be unique to CWE; it has not been handled in [7PK], [CLASP], or [Krsul].
CWE-1000 captures most of the chains and composites in CWE. Since CWE-699 is more developer-friendly, it generally does not specify those relationships, although they are readily visible on the CWE web site.