Just to reiterate that there are large stops to the downside in both USD/JPY and GBP/JPY that we know about, and there could be similar stops in EUR/JPY and AUD/JPY as well. The statement from FinMin Azumi sounded very much as if they will be waiting to talk to other G20 FinMins in mid-October before deciding on a Yen-weakening strategy.
Stop-losses usually get targeted and get done so the most immediate danger would seem to be downside in the JPY crosses.
