A Second-Order Interpretation of the −90◦ Phase Lag at a Relational Coherence Threshold From First-Order Consensus Artifacts to Inertial Network Resonance

This revised note reinterprets an earlier reported (-90^\circ) phase-lag signature in discrete consensus networks. The original observation suggested that a coupling value near (\lambda \approx 1.7) might represent a universal relational coherence threshold. The present revision separates the robust dynamical insight from that overinterpretation. The central correction is that a first-order consensus model does not naturally support a genuine resonant (-90^\circ) phase transition. Apparent quadrature behavior in such systems can arise from transient decay, finite-window spectral estimation, graph-dependent synchronization rates, or reference-node artifacts. A true (-90^\circ) crossing requires an inertial or second-order dynamical container.