The nuance though is the direction in which the market moved. On the day, the market went from 20% for Brexit in the morning to 10% by the evening for Brexit. A

The nuance though is the direction in which the market moved. On the day, the market went from 20% for Brexit in the morning to 10% by the evening for Brexit. And this trend had been in place for about 10 days (ie Brexit losing ground). So you'd think that as an event draws closer, the prediction odds would tend towards the outcome, not diverge from it.