Due to wire time delay, keeping it in a cycle would be difficult to time right with market movements, which is why I've been told this sort of arbitrage doesn't already exist to even out USD/BTC vs CNY/BTC.

Though if you have a counterparty billionaire with USD and a good lawyer, you could set up a deal sort of like mine where enough of their USD is used to buy up all BTC in a market order just below the level of CNY, then you get their BTC sold for CNY, do the forex, and send their mass profit split/USD wire return right away and see if the USD-only BTCers keep dumping their coins to keep the gap wide as the Grand Canyon, or it evens out for a while.