I am a cyclist and I am also a motorist (generally much more the latter than the former).
There are idiot cyclists and there are idiot motorists.
The difference is that an idiot driver has the potential to kill a cyclist / pedestrian / other motorist, an idiot cyclist may well delay a driver by 5-10 seconds or, at worst, put a scratch on a vehicle.
Not quite a balance in cause and effect is it?
Believe me, when I ride a bike, I also go at circa 20mph on the flat and often ride with two or three other cyclists at most. I don't ride in the gutter due to the potholes, grids and general detreitus that make up these relatively 'unused' parts of the road, where most motorists seem to think cyclists should dwell. This is due to the fact that a) it is very uncomfortable to ride in the gutter (the same reason that motorists don't do so) and b) it is not safe, due to the holes / slits / water / leaves / gravel, etc in in this area. As a consequence of this, I would guess I ride about a metre or so out form the edge of the kerb (taking up maybe a third of the available lane) and so almost without fail, every week, I get a blast from an impatient motorist (typically 50+ in age, which I find interesting) who may have to wait 10-20 seconds on windier roads for them to overtake. Would they adopt this behaviour with a tractor, horse rider, pedestrian, etc? No, they do this because in the past they seen a cyclist do something stupid and have now decided that all people on bikes are fair game, conveniently forgetting that motorists themselves are always cutting lanes, running red lights, having near misses, speeding, etc, etc. These peope don't adopt a crusade against all other motorists off the back of this though, do they?
I'm afraid threads like this just reinforces the same old attitudes and gives some people the feeling that they are in the right to treat other road users, no matter what the evidence, with disdain.
Going back to the point of the thread though - I do agree that the education should also be focused on making sure cyclists (typically the less regular variety) don't under cut HGV's or sneak up the inside on the approach to junctions, no matter how tempting. Its stupid and dangerous . Most HGV's now have clear signage on them warning cyclists about this practice and slowly but surely I think the message is getting through.