@I would suggest
You don't get it, do you. Many many times I have slowed to allow safe braking distance. What happens - as you would know if you drove and / or lived in the real world - is someone overtakes you and puts you straight back to square one. Don't you know that? Are you still at school?
The net result is you've gone backwards, which if you're happy with strongly implies that you should just stay off motorways not just for everyone else's safety, but because you're defeating the object of taking them in the first place.
This happens invariably and on any of the busiest motorways this will be happening your entire journey so that effectively you are inviting everyone else on the road to go past; not just being unconcerned that they are but actively inviting them to. So what are you on the motorway for? Because like those ones who drive too slowly you get off on disrupting fifty miles of traffic so's you can feel smug? Do you wear a trilby by any chance?
As for staying in the left hand lane you end up having to all but continually overtake. You slow to about 60 mph - to avoid rear-ending the lorry - then pull out and accelerate to about 80 mph very quickly. Or you're so brainless you force the traffic in the middle lane to brake every time, like, say, you fail to realise how very quickly those cars in the middle lane close on you at 80 when you pull out at 60, so you don't pay enough attention to that mirror. You pull out in front of them safe in the knowledge that they're the ones driving too fast, so if a pile up happens, it's not your fault, it's theirs?
Yes, I know how to drive on the motorways. I covered a quarter of a million miles doing so, on all of the busiest ones. The only accident I was ever in was as a passenger on the M3 when I suggested the driver allow more braking room because his car was about 10 years older than the one in front and if it braked hard we would go into the back of it. He didn't listen. A minute later the car in front jammed its brakes on and we went into the back of it. Our car was a write off but thankfully no-one was hurt and we just spent the rest of the day trying to get back home.
Dear AC, the most dangerous drivers of all on the motorways are the ones continually weaving in and out in and out to and from the left hand lane, like all the other dangerous drivers only they're trying to do it without attracting the attention of the police. The safest ones stay in the middle lane and leave the left hand to the lorries.