If rearranged, do so to emphasize organizational origins. The principle of provenance is basic and inflexible and speaks to the integrity of the archives. Series Created in the course of performing a particular kind of action and embody records resulting from actions of a particular office. Series reflect action, should be treated as integral units. This value as a record of the activities to which they pertain is lost the moment series are not kept intact, e.g. if merged into a chronological file.
Relationship has little effect on evidential value.
Groups, subgroups, series should be kept intact as integral units, not merged. Arrangement of series should contribute to an understanding of the significance of the records and make them intelligible to the user. But this is as relates to series, not individual records. Or, when original order is bad or not easily discerned. The principle of original order relates to the convenience of use.