Journalists usually ask politicians questions in an election campaign to catch them out, trip them up and cause a gaffe. Not this time. I genuinely wanted there to be no story yesterday when I asked Michael Gove a question that matters more than most things. I asked if he could guarantee that nursery schools would not be allowed to charge top-up fees for the currently free places of every three- and four-year old. I asked it this way, that way and the other way. Other journalists joined in, too, but no. He would not, could not give that pledge. I sincerely hoped he would kill the story dead, but no.