May well be the best vid I have seen explaining the charge weights and how the over-emphasis of the chrono ES and charge weight can lead you astray.
Also happens to be a good illustration of how to achieve consistent charge weights, and the value of what you are really seeing on a .1gr scale such as a Chargemaster dispenser, or in the is case, another RCBS Scale, vs an A&D scale.
https://www.youtube.com/watch?v=LecSyrB0BM0