The Decoupling Locus: a MOND Scale Derived from a Clock, and the Solar System Reduced to One Number

A cuscuton-clock sector with a projected-gradient scalar produces a cold clustering component and passes nine gates as a dark component, but produces no force law, because matter in that action is minimally coupled. Adding a coupling is what would give MOND, and the obstruction was that the clock and the scalar mix. We report that the mixing vanishes EXACTLY on the locus W_0 = U - 2 gamma qbar^2 qbardot = 0, a condition on coefficients the action already has. A first pass priced that locus at a cubic coupling eight orders too large, scaling as 1/w; that pricing held the clock coefficient U fixed, and U is not free. With rho = U/m_rel imposed the factor of w cancels identically: the locus fixes the dimensionless ratio gamma qbar^3 H/rho = -1/(6(s_0-1)), of magnitude at most 1/6, and the operator's weight against gravity is Omega/(6(s_0-1)) <= 0.044. THE EARLIER VERDICT IS WITHDRAWN. The locus also FORCES two previously free quantities: positivity requires s_0 >= 2, hence m_rel <= w <= 1e-4. Extending the action by the Y^(3/2) operator identified as missing in the previous paper, plus a leading-order matter coupling, the quasi-static gradient sector yields the deep-MOND scaling outright (dlog g/dlog r = -1, dlog g/dlog M = +1/2) and fixes the acceleration scale, a_0 = lambda^3/(12 pi G beta s_0), mass-independent and FALLING with the clock rate. The single conflict, that the locus wants the linear gradient coefficient large and deep MOND wants it small and it is the same coefficient, resolves into one inequality, C = 2 k qbar^2/U >= 1e3, whose derived exponents cancel exactly, so C is a constant of the motion. Finally, coupling matter DISFORMALLY along the clock's own unit timelike direction shifts both weak-field potentials equally, giving gamma_PPN = 1 exactly with NO added vector field; boosted, the same term gives alpha_1 = 8 f_s, five orders over the bound unless local matter drags the clock to within 4.6 m/s. That alignment, and kappa, are what remain open. This paper also records three corrections to the previous one, found by external audit and reproduced independently: the health condition had the wrong sign and is U > 4 d l; the interpolating exponent was measured against the Newtonian rather than the true acceleration and is 0.997 not 0.470; and the no-force-law verdict was right for a different reason, namely minimal coupling. Ten new Lean 4 certificates; the file stands at 124 theorems, zero sorry. This is NOT a complete theory of gravity. AI-assisted research programme; not peer reviewed.