Certifying Chirality-Authored Spin Direction Change With Signed Triads And 4S3

This note converts the interpretation gap in “Chiral nanowires can actively change electron spin direction” into a falsifiable, protocol-driven claim: the reported same-direction endpoint behavior is treated as suggestive but not self-proving, and the mechanism question (active spin reorientation versus interface filtering/contact artifacts) is reframed as a fixed contract with explicit assumption control, triad fingerprint closure, and audit-grade accounting for missingness and leakage. The contract separates signed decisions from zeros, logs yield loss independently (SoZ/yield), and requires flip-based authority tests (chirality reversal, contact swap, bias reversal, disable baselines) under a leave-one-out audit so that “rotation” is certified only if it survives all knob-equivalent confounds. Strong vs Strong-to-Weak is included as an optional tag to distinguish wide-window, low-tension plateaus from cases that remain viable only with nontrivial structure or tension budget.