This is a procedural error with limited constitutional damage. The separation of powers driver scores 3.5 (governor's veto power temporarily compromised by administrative mistake) and rule of law 2.5 (procedural requirements matter). However, severity multipliers are low (0.8/0.9/0.85) as this is highly reversible - legislature can address through various mechanisms, vetoes may still be valid upon legal review, and it sets minimal precedent as an acknowledged error. Mechanism modifier 1.15 for policy_change, scope 0.4 for single_state. Base score 6.99 × 0.612 severity × 1.15 × 0.4 = 2.59. B-score elevated by novelty (5 - unusual gubernatorial error), media_friendliness (6 - simple narrative, large dollar amount), and mismatch (7 - $11.1B budget drama from clerical error). Layer 1: 9.9, Layer 2: 7.2, final 17.1. With A=2.59 and no clear mechanism of constitutional harm beyond temporary procedural confusion, this qualifies as Noise despite moderate B-score.