We're talking about finding accuracy for hunting rifles here. There are typically two accuracy nodes corresponding to barrel vibrations - one at the top of the vibration cycle and one at the bottom. The OP says he works up in 0.5 gr powder charge increments and finds an accuracy node. No further effort is made to fine tune to the optimum charge weight at the node. We go right into 0.003 seating depth (SD) increments.
I spend more time up front find tuning the charge wt. before tuning the seating depth. 0.3 to 0.4 gr charge increments.
I've never seen a hunting bullet that is that sensitive to SD. A bullet like the TTSX could have a sweet spot anywhere from a 0.04 to 0.12" jump. Fiddle farting around with 0.003" increments is a waste of time, components and barrel life.
I'm not buying to two-shot accuracy vs. seating depth graph either. Statistically insignificant. I believe the graph poster said he felt there was a correlation (actual words were cyclic relationship - whatever that means) between the ES and accuracy, whch I don't see. That correlation is all over the map, er, I mean graph.
To each his own, I guess. Lots of different approaches for finding accuracy in a hunting rifle.
