After importing, MBImport tries to make sure there are entries in the editor table for all editors referenced elsewhere. This is a very slow process (took 25 minutes on rika). Sensibly, MBImport first checks whether the editor table has been imported during this run, in which case the step is skipped.

Unfortunately, the hash for imported tables stores the names of the files, not of the tables; in the case of editor_sanitized and editor, they differ, and so the expensive step is run even when editor_sanitized has been imported.