In some implementations it may be possible to remove versions from within a version history using VersionHistory.removeVersion. In such cases the version graph must be automatically repaired so that each successor of the removed version becomes a successor of every predecessor of the removed version. Note that allowing remove in this context would not constitute an exception to the requirement that the version storage be protected, since protected status applies to standard write methods (e.g. like Node.addNode) and not version-specific methods (like Node.checkin) that alter the version history as a side-effect.