have you looked at other options like data avoidance in the DMG?
ex:
Avoidance
We recommend that you make the appropriate customizing settings for the copy control for sales documents
via transaction VTAA to avoid the document flow and, as a result, keep table VBFA from growing too much.
For more detailed information on how to do this, see SAP Note 105512 (release-independent). Although this
note was written for contracts, the solution it presents can be used for all sales document types whose direct
follow-on document is neither a billing document nor a delivery.
Archiving
Entries from table VBFA are archived via archiving objects SD_VBAK, SD_VBKA, RV_LIKP, and SD_VBRK.
A sales document does not only have a links record to its immediate follow-on document, but to all follow-on
documents in the document chain. Because document flow records are archived together with their preceding
documents, the archiving of orders has the biggest effect on the document flow.
See also SAP Notes:
· 131051 (release-independent): VBFA records remain in the system after archiving
· 647775 (SAP_APPL 46C 603): Missing test flag for report ARCHVBFA
· 74513 (SAP_APPL 300 - 500): Correction program: document flow for non-existent delivery