It is still on the agenda, if you believe comments this week from Hong Kong officials, possibly timed to coincide with China's annual three-day Central Economic Work conference, which ends on Wednesday in Beijing. Hang Seng stocks have been bouncing all week – few more than the market operator, Hong Kong Exchanges and Clearing, up almost a quarter since the weekend.

The excitement is probably misplaced. It is unlikely that a project that started out as an effort to drain some of the excess cash from a super-heated Chinese economy would be revived at a time when growth, not inflation, is the problem. What is more, average daily transactions on the Shanghai exchange have steadily fallen all year, suggesting that China's budding day-traders are hurting almost as much as the Taiwanese after the collapse of the technology bubble. There, the ranks of active amateur punters have thinned by about two-thirds in eight years, while the index has never come close to recapturing its highs.

In pure valuation terms, the beaten-down Shanghai index is now a lot closer to Hong Kong, at about 16 times trailing earnings, versus 11. But that gap is still big enough to discourage a loosening of capital controls. Why would an investor want to buy an A-share when he or she could get the same economic benefits from buying an H share a third cheaper? The depreciating yen makes the maths even more attractive.