NVP,
Asia has been shorting the JPY for a long time now, though it has gained some strength over the past few months or so. The persistent Asian shorting of the Yen, against being Long in Gold, has also fallen apart of late.
Don't you find that just when you locate a real correlation throughout the hundreds (maybe thousands) of possible combinations and pairs out there, that it disappears into the ether or begins to decay to the point of being unreliable?
I try to look for internal JPY "correlations" - using the word sparingly, of course. I'm trading the seven (7) largest cross pairs in the Yen and often times find one or two of them lagging the basket. Sometimes that lag can be several dozen pips in size. Occasionally, Australia and New Zealand team-up and diverge from the bunch, creating an opportunity. Sometimes, USD and CAD will do the same thing, while typically GBP/EUR/CHF will run pretty much in sync with each other.
I find that trading the "Magnificent Seven" (as I call them) gives opportunity for heading as well, when you are forced to deal with FIFO rules. You have to get the sizing correct, however. Of course, not each pair has the same cost and not each pair moves with the same daily range.
Spend some time with all seven of them and you'll note some interesting internal behaviors that give rise to opportunities intra-day.