JontyB: was taught from day one to treat all other drivers like idiots and not to expect anything.
I'm sure you were taught to treat other drivers as 'hazards', rather than 'idiots'. As, logically, they will be, as they should be, treating you as a hazard. Thus, you will all be ready to expect anything and be ready to deal with it within the realms of your own expertise.
I find these 'surveys' of very little importance. Particularly, when then select a section of the driving community for special attention whether they deserve it, or not. Many use these misguided references to section of motorists to divert attention from their own weaknesses behind the wheel. We all have our moments on the road.
Rather than sidelining an group of drivers, who are just a small part of a bigger group, we should consider our own driving standards. To fall into the trap of considering one group worse than another makes you no better than they are. From this, good manners will fall into place.
Like all things in life, driving is no different. Respect engenders respect in others.
...'T'is too much proved, that with devotions visage and pious action, we do sugar o'er the devil himself...