Market perceptions, whatever they are and whatever their influence over oil prices, take a long time to change.Analysts blame perceptions when prices contradict their forecasts. And since all analysts have been wrong at least once about oil prices, many of them worry about the extent to which perceptions influence markets.Yet it’s no great mystery. Perceptions are all that buyers and sellers of oil have to work with. Some perceptions are just better than others. And some are acted upon with better timing.Market perceptions embedded in public consciousness turn slower than a laden tanker.Politicians in the US, for example, keep promising to rescue Americans from $4/gal gasoline. Yet ...