Atticus, You did not take time to read me, I wrote" I am not talking of arb nor collar" that's may be not crystal clear english as english is not my mother tong also you are too experienced to beleive you may have missed or not know something Anyway I gave up posting in this forum long ago, too many smart guys taking others for idiots and others ideas for BS, yesterday was a mistake, I prefer to read it occasionaly and make-up my mind myself. So you found a free lunch at 17% per 2 weeks exploitable since long, dont you call this a free lunch, off course not they dont exist.
It's not a common arb and the discussion was limited to the conversion market. Feel free to trade conversions on the GBPJPY and let us now how you do. If you're not referring to the conversion, what exactly was your question?