DCRP64 / X72R47: Constant-Defect Null-Channel Exclusion and Forced Pressure Increment

Building on DCRP63's reduction of the X branch to two cases — 'spatial oscillation of the pressure-response defect' versus 'the defect trapped in X72 Round38's spatially constant null channel, with the stretching eigenvalue instead paying the cost via temporal Floquet modulation' — this round proves the second branch impossible: on the aligned/no-flip finite-compensation branch, any spatially constant traceless tensor is orthogonal to B by isotropic covariance, so if the null channel held it would force the neutral stretching rate to satisfy λ'+λ=−M₄/6Z<0, which, once integrated over one DSS period, contradicts the period-averaged neutrality condition. This closes X72 Round38's N1 (δE_p=0) null channel, proving that the aligned branch must carry a strictly positive, cumulatively increasing pressure-defect budget, leaving N2 (δq=0) and N3 (δV=0) for DCRP65 to handle.