Mark Carney could just as easily have shrugged his shoulders and declared that, like the rest of us, he hasn’t a clue how Brexit will work out. Instead, the Bank of England governor, obliged to riff on a theme when unveiling new economic forecasts, opted for “the fog of Brexit”, which amounted to much the same thing. Sadly, he couldn’t say when visibility will improve. Financial markets, too, seem baffled. The headline news that the Bank was making deep cuts…