The point of this presentation Is diversity in the cover crop resulted in increased carbon in the soil over any one cover crop at the same density. Different plants feed different parts of the soil biome.
They started slowly adding more diversity but discovered that was not necessary, The process can be instituted very rapidly. Then they went to inter planting support plants with the potatoes so that the diversity would be there for beneficial predatory insects. Farmers are taught to fear root competition but in actuality more diversity of roots is complementary resulting in increased yield.
I have experienced being on a potato harvester where the driver was told to try a pass in this field and if the yield was to low to skip it and go to the next field which did not have the weeds. The field with the weeds had the better crop.
The diagrams of the interlocking cycles of chemical farming creating pest and disease problems contrasting with diversity without chemicals solving the same problems is worth watching the prresentation alone.