X72-18: Weighted Strain-Vorticity Obstruction Confluence

Continuing from Round 17's critical weighted physical-gradient carrying quantity E_M (whose finite space-time integral would control Q), this round decomposes E_M exactly into longitudinal/tangential strain-vorticity components, proving that the base carrying quantity W_SV satisfies W_SV≤E_M≤2W_SV, with the directional-misalignment term nonnegative and inessential for budget equivalence. From this it proves the chain: critical blow-up of Q ⇒ divergence of enstrophy dissipation ⇒ divergence of vortex-line stretching ⇒ divergence of positive middle-strain activity, which brings this long route — developed out of the quotient/Hodge line — back into confluence with the original strain-vorticity obstruction core of Round 03, forming an 'obstruction confluence loop' rather than a circular argument, since new necessary structure (gauge, curvature, continuous danger layers) was acquired along the way. The route halts at STOP-C22 (weighted-enstrophy / vortex-line-stretching return gap), passing the baton to the next round to launch a dual-path coupled attack on the confluence core.