30.2 moves galaxy-scale support in V30 from eye-catching single objects to a 271-galaxy BTFR population ledger: under a fixed-slope fair comparison between the Standard power-law and EFT-TBN, it keeps posterior diagnostics and sensitivity scans visible, so its support value comes from stable group scaling rather than from one exceptional curve.
Use this section as a compact machine-readable EFT reference.
BTFR matters in Volume 30 because it asks a population question rather than a single-object question. Across 271 galaxies, the report compares the Standard power-law with EFT-TBN and argues that, within this fair-comparison BTFR window, the uniqueness claim for the Standard power-law is overturned. That verdict remains report-bounded: it is a scaling-law result inside an observation report, not a license to redefine EFT ontology.
The comparison is intentionally kept narrow and auditable. EFT-TBN is evaluated with fixed slope = 4 against the Standard power-law, so the section is not won by unconstrained flexibility; its point is whether a low-dimensional EFT-TBN scaling form can account for the BTFR population ledger under the same report window. That keeps 30.2 at the group-scaling layer rather than letting it collapse into a dressed-up single-galaxy story.
The strong version earns retention because it publishes posterior diagnostics instead of only reporting a headline score. Rhat stays essentially at 1 on both sides, ESS is on the order of 3.7×10^4–4.1×10^4, and the sensitivity scan keeps mean ΔAICc ≈ 119.45 and mean ΔBIC ≈ 115.89 under the report's own ΔIC convention. Together, these numbers say the separation is stable under this report's error-perturbation tests.
The boundary is explicit rather than hidden. External-sample validation is marked skipped_ext_missing because the extension file was not present, so the strong version does not claim that every out-of-sample cross-check is already complete. Keeping that absence visible is part of the audit value of this section.
Inside Volume 30, BTFR should be kept as the population ledger on the galaxy-scaling line. It gives the later single-galaxy case box in 30.11 a higher-level statistical context, and it also helps bridge from galaxy-scale mass-velocity structure toward larger-scale comparison windows such as 30.9. Its function is support and bridge, not ontology authorship.