Is it possible to apply a workflow to concept deletions?

All deleted concepts (which actually will rather be deprecated than ultimately deleted in order to keep the URIs 'reserved') can be 'reactivated' from within the workflow dashboard. At the dashboard the full history of deprecated concepts can be looked up, and it can be put into the 'Suggested Concept' area from where it can be re-assigned as a narrower concept or an alternative label of an existing concept.