What's the price of tea in China with Bitcoin?

When exploring markets for potential (tradeable) inefficiencies sometimes finding none is just as interesting.

Americans used to be able to trade the USDCNH on FXCM before they got taken down. The dollar/yuan cross has remained interesting for the last couple years but has been somewhat non available to US forex traders. I wanted to look into the possibility of trading moves using Bitcoin as a proxy.

Looking back at a potential setup in 2016 the move in the USDCNY would have yeilded about 1.65% . During the same time BTCUSD and BTCCNY moved 10.9% and 13.3% respectively. From said move until present writing the moves would be USDCNY 3.35%, BTCUSD 78.88%, and BTCCNY 72.52%.

So did I find a potential arbitrage trade of 1-2%? Not hardly. The concurrency exchanges that would facilitate this sort of trade operate on expiring futures products that may or may not follow the underlying perfectly. More importantly, holding these products would accrue significant carrying costs. One month could easily eat up that 1%.

What the relative efficiency and the small 1-2% inefficiency tells me is that there are already market makers keeping everything closely correlated while staying profitable within that small margin.