DCRP82/X72R65: Codimension-Two Trace Barrier and the Kelvin Concentration Defect

Continuing from DCRP81's reduction of the Kelvin residue to the subgrid-scale circulation flux K^sgs_ℓ and its proposed plan to absorb this via tubular thickening into the existing volume-type commutator detector, this round tests whether that absorption holds unconditionally. It proves that it does not: it constructs an explicit codimension-two kinematic counterexample — a function that concentrates near a curve, with O(1) line-trace mass while its tubular-normalized volume mass tends to zero — showing that no universal trace-to-volume inequality can exist. It derives the exact factorization S̃_C=Θ_tr·S̃_T, where Θ_tr is a dimensionless codimension-two trace ratio, and shows the absorption goes through only under the additional assumption Θ_tr≲1 — an important correction to the D81 plan. Conclusion: the Kelvin terminal problem reduces to R_K⟹S̃^(4)_active∨R_tr∨known material noncompactness; the second-order viscous mystery has been reduced in order to a first-order material line-trace concentration problem R_tr, left for DCRP83 to test whether Θ_tr→∞ forces a finer active transverse scale.