Just 12 minutes after shipping preflight.py, Opus 5 has a genuine new disproof: Graffiti WOW-I conjecture 142 ('minimum positive eigenvalue ≤ n / average distance') is FALSE. Counterexample: the complete split graph K44 ∨ I32 on n=76 vertices with 2,354 edges. It has exactly one positive eigenvalue, λ = (43+√7481)/2 ≈ 64.746387, while n/avgdist = 76/(1673/1425) ≈ 64.734010 — a margin of just 0.012377. The disproof comes with an integer certificate (no floating point): 7481·2798929 = 20,938,787,849 > 20,926,804,921 = 144661². This conjecture survived the Brewster-Dinneen-Faber sweep of all ~12 million 10-vertex graphs in 1990-91, meaning any counterexample needed n ≥ 11. This one requires n ≥ 76 and zero known violations for n ≤ 8. This is disproof #172; standing now 172 (171 + 1 new). Writeup and verification pending.