Nothing I read in that article indicates that managers got their tactics from the slave owners. It could be that managers came up with these tactics based on the free market just as much as the slave owners did (both had the same pressure of increasing profits), so it was convergent evolution, not that the managers inherited ideas from the slave owners. Incentivizing workers isn't a completely nonobvious idea anyway; it isn't as if issuing incentives to workers has to mean that the managers got their ideas from slave owners.
I'm not sure that it's meant to imply that they got their tactics from slave owners; I think it's intended to demonstrate the comparisons between current, and 200 year old business intelligence / reports / and what we today call analytics. One could fairly reasonably see the correlation.