DCRP60: Rank-Two Closure Package and X72 Frontier Selection

Building on the rank-two rigidity closure package accumulated across DCRP38–59 (including the DCRP59 signed-residual confluence, which is not itself archived in this folder), together with the pre-NTLA rank-two frontier from RMRM checkpoint v42 and the visibility theory of X72 Round37 and 42–43, this round conducts a formal closing audit of the entire rank-two equality track. It proves that the maximally rigid rank-two branch has no zero-defect global continuation: any continuation must fall into one of three channels — X (X72 visibility/pressure-response defect), N (non-affine vorticity stretching), or T (inward vorticity turnover). The audit further finds that N and T are in fact a recurrence of DCRP35's old stretching/turnover dichotomy under a stronger quantitative lower bound, forming a loop, and that the only genuinely new coordinate not absorbed by this loop is X. STOP-D60 therefore formally closes the rank-two subproject, selecting the coupling of non-affine stretching with X72's nonlocal stress projection as the new frontier and handing it to DCRP61/X72-R44 — the round text states plainly that rank-two local geometry is now exhausted and that the only new observational coordinate able to break the loop comes from X72, from which point the combined DCRP/X72 round numbering formally begins.