Measured halo concentrations scatter far beyond the gravity-only prediction: dwarfs run cored where cusps are demanded, some clusters run startlingly over-concentrated, and the variance at fixed mass dwarfs the simulated scatter (Bullock and Boylan-Kolchin 2017; Kaplinghat 2016). Mass and accretion history are the model's only dials, and two dials cannot make this much diversity.
A collisionless particle gives every halo the same physics, so concentration must be a function of mass and formation epoch alone. The observed variance therefore requires a third dial, and the candidates on offer, tuned feedback, self-interactions, warmth, each import a new sector to supply what the particle picture lacks.
SCT owns the missing dial natively. What concentration measurements actually probe is the radial profile of the effective gravitating mass, and in SCT that is the baryons amplified by the coherent mesh, A(N, σ_v, R), governed by each system's coherence state through C = exp[-σ_v²/v_cross²] (P50, P52). Coherence varies system to system with kinematic history: quiet, comoving-rich systems amplify strongly and read as concentrated, kinematically stirred systems amplify weakly and read as cored or diffuse, and the variance at fixed mass is the coherence distribution showing through, the same single dial carrying rotation-curve diversity (recid 112), the dwarf cores (recid 127), and the dark-matter-deficient diffuse galaxies at the decohered limit.
The over-concentrated clusters complete the pattern from the other end: systems with exceptionally coherent substructure amplify beyond the mean, the same enhancement behind the cluster lensing excesses, while no particle cross-section must be tuned to behave oppositely in dwarfs and clusters, because coherence naturally runs the full range. The registered diagnostic is kinematic: concentration residuals from the mass-only relation should correlate with each system's σ_v/v_bulk coherence measure, not with feedback proxies. The formalism is in Paper 13, From Chaos to Coherent Gravity, with the superposition mechanics in Paper 6, From Chaos to Cosmic Collisions.
Keystone economy: P52 supplies the dial, P54 removes the particle whose universality created the problem.
The registered kill: if concentration residuals across large samples show no correlation with kinematic coherence diagnostics, while correlating instead with feedback indicators like star-formation history, the coherence dial is refuted and the baryonic repair stands. The cluster end cuts separately: over-concentrated clusters whose excess proves attributable to line-of-sight projection rather than genuine amplification would remove the high-coherence tail the mechanism predicts.