Listening to the radio interview, the guy from the Advisory Board made it sound like it was not suppose to be taken to mean that slavery was good. I just read through the Standards and unbelievably it does use the term personal benefit. It was a "clarification" to the topic. Definitely bad wording. I have a feeling that Donalds will get his wish for a re-write of this one:
SS.68.AA.2.3 Examine the various duties and trades performed by slaves (e.g., agricultural work, painting, carpentry, tailoring, domestic service, blacksmithing, transportation).
Benchmark Clarifications: Clarification 1: Instruction includes how slaves developed skills which, in some instances, could be applied for their personal benefit.