That was why GE2017 was seen as such a shock
Given what happened on June 8th last year you would have thought people would have worked out by now is that you cannot look at the next election by thinking back to the last one and applying the same sort of judgements relating to what happened.
So currently you will find from many committed Corbyn supporters saying that their man is going to sail through, whatever the polls might be now, because they remember what happened last year.
In fact one of the reasons why the last general election proved to be such a disaster for those in the prediction business was that people were looking at it through the prism of 2015. There was this widespread assumption because the polls had overstated Ed Miliband’s two years earlier than they were doing the same again.
One thing I would say is certain is that we cannot assume that the Conservatives will run as poor a campaign as Theresa May did. Whoever is the CON leader, for instance, is not going to produce a manifesto with all the hostages to fortune and many more people in the party are going to scrutinise it in detail before it is signed off.
Another thing you can be sure of is that whoever is the Conservative leader will go into the TV debates well briefed and well prepared and will not allow anything like the mess ups of last time
We also have a LAB leader, who looks a lot more damaged today than he did at the end of the year. His handling of the Salisbury incident and the charges of anti-semitism have surely, been what has led to the drop in his personal ratings in latest polls.