To the extent people are trying to trade on this model, they look for liquid marketplaces that are exposed to China's economy. Australian metals and mining stocks, for instance, or currency fluctuations in closely-pegged economies (forex being pretty darned liquid with a very deep futures market).

Chinese equities are something else entirely, closer to a derivative class. And hard to trade in directly (not that I have tried or would ever try -- I'm in index funds).

And the truth is, the banking system is less liquid, and the equities market much smaller, than developed economies. Oh, also, short-selling is illegal, I believe.

So no, there aren't any natural, market-driven checks on this stuff.