The Bank of England's long-awaited announcement on monetary-policy guidance had something to disappoint everyone.

Markets initially embraced the idea that Governor Mark Carney had engineered rates at 0.5% for years to come-with policy to be revisited only if the unemployment rate falls to 7%, which the BOE thinks might not occur until late 2016. But doubts quickly arose about Carney's apparent policy coup. Those doubts are likely to plague the BOE and test the new governor's credibility.