Not sure I agree about the middle lane business. The inside lane is usually full of lorries doing their regulated 60mph or so. That also tends to be the most worn carriageway. With the best will in the world it is sometimes hard to change lanes when they are all full! It seems to me that the managed motorways are effective because they turn the motorway into streams of traffic travelling at almost exactly the same speed. Often the problems on an otherwise unobstructed motorway are caused by a car suddenly changing lanes - quite often for an imagined minuscule advantage - which has a knock-on effect behind and eventually leads to pulsing and a standstill for no real reason. Indeed, when the "managed" thing is functioning there is often a sign saying "stay in lane".
Like much of our road system in our overcrowded island, motorways are effectively a 60 or 70 mph traffic jam. Or a 10mph traffic jam if you are in London. Driving a car is a miserable frustrating business most of the time and does not accord with the visions of freedom and power featured in the car adverts. This might explain the appeal of cycling for us, and possibly the enviousness the car-trapped feel when they see our freedom.