Beijing is too savvy – and interventionist – to allow that to happen. First of, rules drafted in 2006 are couched around with enough caveats to ensure only the most determined short sellers make it through the net. Stock can only be borrowed from a small clutch of brokers, a group not renowned for holding huge quantities of shares. Not all shares can be shorted. Worse, according to local brokers, only certain categories of investors will be able to short. This could exclude domestic mutual funds and the handful of foreign investors able to buy “A” shares. And should the whole experiment go horribly wrong, there can be little doubt that Beijing will nix it overnight. These are the regulators, after all, who increased stamp duty and equity issuance as the stock market bubble inflated, and took reverse steps once it burst.

Secondly, Chinese regulators know what some of their western peers seem to have forgotten: short selling is good for markets. Improving efficiency and liquidity is especially key in a market prone to boom-and-bust cycles. Allowing investors to bet on a falling market, rather than simply exit, should keep turnover levels off the floor. Steering the stock market onto the path of greater sophistication, while reserving the right to micro manage the process or even backtrack, is a very Chinese solution. Of course, in the current climate that may be no bad thing.