"Galactic Loads as Bank Stabilizers: Triadic Elastic Backreaction and the Higgs Auto-Brake in R⁸"

(Note IV: Bank-Elastic Stability + Higgs Auto-Brake) We develop a minimal *Bank-elastic* stability model for the R⁸ / Crystalline Axiverse framework in which the hidden “Bank” behaves as an elastic medium whose effective stiffness and damping are **renormalized by 24 phase-leaves** (our universes). The leaves are organized in a **phase ring** (not geometric positions) and partition into **8 triads** \(\{t,t+8,t+16\}\), capturing *triadic rigidity*: tight internal phase-locking within each triad, but potentially decohered behavior across triads. In the linear-response regime, a Bank collective mode \(x(t)\) is described in frequency space by a propagator \(D(\omega)=\Omega_B^2-\omega^2-i\,2\Gamma_B\omega-\Sigma(\omega)\), where the leaf backreaction enters as a complex self-energy \(\Sigma(\omega)=\sum_t \Sigma_t(\omega)\). Each triad contributes \(\Sigma_t(\omega)\propto p_{\rm eff}(\omega)^2\,\chi_t(\omega)\,e^{i(\omega\tau_t+\phi_t)}\), combining: (i) a **7-Seal response filter** \(p(\omega)=\prod_j \omega^2/(\omega^2+\Lambda_j^2)\), (ii) a triad susceptibility \(\chi_t(\omega)\) (modeled as a light triad-average mode plus heavy relative modes), and (iii) a **phase-lag (delay)** \(\tau_t\) in the leaf→bank→leaf loop. This delayed feedback can rotate the complex response and generate **effective gain** bands, i.e. “flutter,” when the effective damping \(\Gamma_{\rm eff}(\omega)=\Gamma_B+\mathrm{Im}\,\Sigma(\omega)/(2\omega)\) becomes negative. A key structural result is a clean stability rule: **coherent, narrowband, phase-locked triads raise flutter risk**, while **decohered/broadband triads add damping and suppress flutter**. In other words, *tight within triads* can coexist with global stability only if the ensemble across triads is sufficiently dephased or broadened. We then introduce the Higgs sector as a leaf-side **phase stabilizer (“auto-brake”)**. Because the dangerous loop contains delay, stabilization benefits from a local dissipative channel with negligible delay. We model a Higgs-side self-energy contribution \(\Sigma_H(\omega)\) (with \(\tau_H\simeq 0\)) and, crucially, an **episodic auto-brake** that activates only during coherence episodes detected by a sliding-window \(Z_3\)-type statistic with hysteresis. This yields a time-domain toy damping map \(\Gamma_{\rm eff}(t)=\Gamma_B+(k_{H0}k_H)\alpha_H^{\rm eff}(t)-G_{\rm gain}u(t)a(t)\), where \(u(t)\) gates coherence episodes and \(\alpha_H^{\rm eff}(t)=\alpha_{H0}+\alpha_{\rm boost}s(t)\) provides proportional stabilization. Calibrating one toy time unit to the SM Higgs lifetime \(\tau_h^{\rm SM}=\hbar/\Gamma_h^{\rm SM}\) allows a MeV-equivalent figure-of-merit for stabilization: \(\Delta\Gamma_{\rm boost,eq}=(k_{H0}\theta^2)\alpha_{\rm boost}\Gamma_h^{\rm SM}\), using a mixing-squared visibility map \(k_H=\theta^2\). Scanning the PASS boundary (no negative-damping time) yields an approximately constant **absorptive-budget plateau**:\[\Delta\Gamma_{\rm boost,eq}^{\rm plateau}\simeq 20.62~{\rm MeV},\qquad \sigma_{\rm rob}\simeq 1.24~{\rm MeV},\]with 68% interval \([19.54,21.98]\) MeV and 95% interval \([17.58,22.20]\) MeV in the calibrated toy. This plateau quantifies the *effective absorptive capacity* required for episodic stabilization of an elastic Bank loaded by triadic leaves; it is **not** a claim of direct time-modulation of the SM Higgs width, and any physical implications would require explicit mapping to off-shell Higgs processes or rare decay channels. **Abstract (Version 2 update).** This revision refines the reporting of the “MeV-equivalent absorptive budget” plateau in the episodic Higgs auto-brake toy module. The plateau is now presented as a single boxed estimate with an explicit robust uncertainty and both 68% and 95% empirical intervals, improving one-glance interpretability and reproducibility. In addition, we introduce a calibration-robust dimensionless brake ratio, λ_brake ≡ ΔΓ_boost,eq / Γ_h^SM = (k_H0 θ^2) α_boost, which isolates the governing parameter product independently of the chosen lifetime-to-MeV calibration. Finally, the interpretation language is tightened: ΔΓ_boost,eq is a calibrated width proxy (a figure-of-merit for absorptive authority in the toy dynamics), conceptually aligned with dissipation as the absorptive part of a retarded self-energy, and is not a claim of literal on-shell time modulation of the SM Higgs width. No other sections are materially altered.