Maintaining focus on an issue is easier when it comes with a snappy, emotive label. Flash orders or dark pools just sound dubious, as does any variant of “naked” trading. The uptick rule, in contrast, suggests a fine, upstanding piece of regulation. Established in 1938, the rule limiting short selling of stocks when their last move was down was abandoned in 2007. However, it is set for a post-crisis comeback. The US Securities and Exchange Commission this week requested additional input on an alternative rule, to allow short selling only above the prevailing best price.

By focusing on prices rather than movement, the rule would, in theory, be simpler to monitor. But the SEC – buffeted by politicians demanding action – has taken an idea and supersized it. Some large stock exchanges in March proposed that such a rule apply only after a stock experienced a precipitous decline, triggering a so-called circuit breaker. In a fevered atmosphere abusive trading becomes more likely so it makes sense to slam on the brakes. But as a permanent fixture this rule would be an unhelpful drag, hampering short selling’s role in greasing the market’s wheels and aiding price discovery.