Quote from cabletrader:
An 'interesting' (lol) strategy, but why pick such a low (and getting lower!) yielder like USD? There's talk of 80 on dollar/yen before BOJ intervention, I guess you need to have either deep pockets or small positions to avoid a margin call, there's no way you could ever risk the trades being liquidated. Also, the interest rate differential is narrowing on Usd and Yen, I'd prefer something with a bit more room to maneuver.
I read a while back about a similar strategy that hedged with a non-interest non-commission Islamic broker (interest arb) which made some decent risk-free returns with the use of high leverage.
I think it gets too complicated that way, it's simpler to do what you're doing and average into a yield positive trade with a high yielder, earn interest every day on leveraged money, and then eventually make a capital gain on the trade itself. It needs less capital, is very low maintenance, and is guaranteed risk-free money as long as the broker doesn't have hidden charges like non-activity fees or commissions.
I did a similar thing a while ago when I got filled on an order on Usd/Jpy that I had already cancelled. The broker wouldn't cancel the trade so I said wtf, just leave it and add as it goes lower and get the interest every day. Within a couple of months the trade came right but I made sure I had enough to fund the account and support the unrealized losses and margin for as long at it took.
Another idea might be to use an automated 'grid trading' strategy which trades the same yield positive direction but takes small profits on positions and then re-opens the trades. The end result is the same except for the extra profits along the way which go towards paying margin on existing positions.