To wonder how so many people are comfortable breaking the speed limit?

If you think that, you shouldn't be driving

There's an argument that you only get speeding tickets if you are not paying attention.

A lot of people who exceed the speed limit don't get speeding tickets. Because when they see something that is likely to clock them they slow down.

Some people would argue that this level of attention is necessary for driving at any speed.

This is quite eye opening. People clearly feel that the speed limit on motorways is wrong and therefore it is ok to break that law. It does make driving more challenging when everyone decides their own rules based on how tgey rare their own competence and their own opinions on when speed limits were set. The rules of the road work best when we all follow them.

I do the same as you. If I am driving faster than the other cars I stay in the right lane until there is space for me to move over. I have absolutely no issue moving over and letting other people pass if they want to drive faster than the speed limit. It’s not up to me to police other people’s speed.

I speed on motorways (though am conscious of where the speed cameras are on "smart" motorways). I overtake and move back into the appropriate lane. I don't tend to do more than 85mph. I cannot see how I can drive perfectly legally on a 2-lane motorway in France at around 82mph (130km/h) whereas suddenly that's dangerous in the UK?

The 70mph was introduced decades ago when few cars could even reach those speeds. It should be updated. Clearly everyone needs to be aware of stopping distances etc, but I have driving slowly.

Rightly or wrongly, most people work on the basis that cameras won't be triggered and the police will not stop you if you are 'only' 10% over the limit. That's 77mph on most dual carriageway/motorways, and given that no car speedo under reads, means that most drive along at an indicated 80 mph. In my experience those going significantly faster are much smaller in numbers - and I drive 25/30k miles a year.

There are two key problems that I see al lthe time. One is that for every 10 people doing an indicated around 80 (with little or no chance of prosecturion for sensible reasons) there's one that sits at an indicated 70mph or less, which is probably an actual speed as low as 58mph or even slower, that then annoys all the lorries trying to get around, and means that there's a 20 mph differnce between them and most other cars.

The second problem is that theres a bunch of drivers who are incapable of maintaing a constant speed even on a quiet road (these are aften the same people that speed up when you move out to overtake them...), so cars that are drving at a constant speed find that they are overtaking the same cars time after time - and constantly having to change lane as a result

Agreed. And there's no such thing as the fast lane

OP is driving with the flow of traffic, she's going into the outside lane and overtaking people in the middle lane going slower than 70mph and then returning to the inside lane.

She's doing nothing wrong

HGVs and some other vehicles are limited by law to 60 mph and/or are fitted with speed limiters. HGVs are not allowed in lane 3 on a three-lane carriageway.

So if you're doing a steady 70mph (while conditions allow) then you're going to have to either slow down or overtake these at some point and might need to accelerate above 70 for a few seconds to safely pass.
You should still pull back in as soon as it's safe to do so.
Don't get me started on HGVs blocking lane 2 for miles on end on two-carriageway motorways like parts of the M11 because they're determined to overtake another lorry that's going one mph slower, but they then haven't got the oomph to get past. Especially on hills. Causes long, slow queues and much frustration.
There is a short, hilly stretch of the M11 which bans HGVs outright in lane 2. It's widely ignored, often by trucks with foreign plates, and is especially chaotic.
Rant over.

The op is perfectly entitled to be in the overtaking lane going at the speed limit if they are overtaking

I love these threads, you either get a thread that says "I have a speeding ticket" and everyone jumps on with the, you shouldn't be speeding, you've broken the law speeches. But then someone makes a thread about driving to the speed limit and everyone jumps on telling them they are a slow dangerous driver who should be banned from driving on the motorway! Honestly you couldn't make it up

No. Read again. Drive with the flow of traffic.

You going 70, I've been driving well over 30 years.

70 is the limit, you shouldn't be exceeding that to overtake. Of course there's going to be people going slower in the middle lane sometimes, it's perfectly acceptable to overtake at 70 to pass them

I'm amazed at the comments on this thread - I guess mumsnet has more of the BMW drivers than the average population! It is absolutely correct to not exceed the speed limit. I notice those who speed on every road don't mention pedestrians - I doubt your advanced driving certificate is going to help you inflict less damage on a child who's run out in front of you if you're doing 40 instead of 30.

Every time I read a Mumsnet driving thread I feel a little less safe on the road

But bloody slower 😆. You over take faster speed than 70 then pull in again. Or even better stay out that lane.

One of the main ones will maintain the distance to with the car in front and brake/speed up to the set speed automatically.

Oh yes we have that. On the one hand it’s bliss. On the other hand if someone pulls in the gap 😱 seriously clunky emergency breaking! It is fast! And it is quite unnecessarily severe. But I do think it was designed to try to save you. It also can swerve for you which is crazy also. Collision avoidance that one’s called 😱