"Which is why we "small-amounters" need a bit of help from our representatives to explain to us what we small-amounters don't know and can't grasp."
That's not so. In the case of a referendum (whatever the subject) it is the job of representatives to present their cases to the electorate to the best of their ability (which was done prior to the EU referendum). If matters are so complex that they cannot be grasped by Joe Public it is the job of both sides to make them easy to understand. An analogy can be drawn with a jury. Much of our law is complex. It is the job of the advocates to put their case, explaining how they believe the law fits their case.
Your explanation of "opinion" is misleading, Gromit. People were asked whether they believed Begum should have her citizenship withdrawn. They were told that such a move would be lawful (because it was said she had dual citizenship) and they gave their opinion. That opinion does not become "wrong" if it transpires that citizenship could not be withdrawn.