TRGB was the neutral arbiter that split into camps: Chicago-Carnegie calibrations land H₀ near 69.8 (JWST-only: 68.8), independent recalibrations of the same data land at 71.5-to-73, and the fine print, tip detection, anchors, extinction, color terms, has been litigated to the percent level. The buried headline survives every dispute: the methods agree on distances at one percent while H₀ fans across the full tension range with the choice of supernova hosts.
One global H₀ forces the fan-out to be somebody's error: if distances agree and answers differ, the host-selection dependence must be bias, and each camp audits the other's admissions criteria. The model cannot entertain the structure the pattern shows, that the answer depends on which galaxies, in which environments, the assembly samples.
SCT reads the TRGB wars as a measurement of sampling geography. The distances are sound, stellar physics vindicated at the percent level across methods, and the H₀ spread rides on the supernova-host step: each program's host subsample weights the Λ_eff field differently (P17, P19), with selections leaning toward the enhanced inner volume landing high and selections diluting it landing toward the global value, the same structure registered in the JWST prior-contamination entry and the Pantheon+ residuals. A genuinely inhomogeneous expansion field guarantees that honest teams with agreed distances will fan across 68-to-73 as their host admissions vary, which is the observed sociology of the dispute rendered as physics: nobody's rungs are wrong, and everybody's number is a weighted average over a real gradient.
The resolution is testable inside the existing programs: re-deriving H₀ from any TRGB calibration with hosts stratified by environment should show the systematic 0.5-to-1 percent cluster-versus-field offsets of the frame-tree layer (P10) and a monotonic trend with host-volume depth, converting the fan-out from controversy into the gradient's cross-section. Foundations in Paper 1 (P17, P19) with the frame-tree corrections of Paper 2, From Chaos To Common Ancestry.
The premise bill stays at zero: this is the third consistency check (after the Cepheids and the chronometers) that the Hubble mechanism passes without new machinery.
The stratification test cuts cleanly: TRGB-anchored analyses with environment-stratified hosts finding H₀ independent of host environment and depth at the 2σ level, the fan-out fully traced to identifiable calibration errors with one camp simply right, would remove the field-sampling reading. SCT requires the host-selection dependence to survive every calibration fix, because it is not an artifact of the rungs.