If the war had been avoided, plantation managers would soon have realized that freeing the slaves and hiring them, with share-cropping relationships, would be cheaper than maintaining a costly system with expensive slaves that had to be fed, housed and maintained in order to keep them picking their 200 pounds. Moreover, the labor force could have been supplemented by the large number of poor whites.

No, I haven't really thought about this, but I remember it from a history class long ago.