Makes interesting reading

I'm similar. below 80 or so i get bored and start daydreaming. but at a higher speed i keep my mind on whats happening on the road.

our 70mph speedlimit was made up overnight to fulfill a need they didnt know was there when they made the motorways, and seemed 'fast' at a time when most cars couldnt cruise continually at 70mph anyway. these days, its quite pedestrian.

I'd have to agree.

The way modern cars are built, you're so far removed from what's actually happening, due to all the driver aids and increased comfort/sound deadening etc that the perception of speed is reduced, as is the amount of driver input required. With less work for the driver to do, there is more chance of daydreaming or distraction leading to incident.

The more stimulus, which higher speeds provide, the more concentration required.

I'd also consider the argument for an increase in adrenalin due to the 'excitement' of driving faster, which helps combat fatigue/falling asleep at the wheel!

See, I'm one of those people who quite happily sits in the slow lane at 60mph for hours at a time, and don't all my friends know it.
Passengers are always telling me to speed up and I always tell them where to go. That's in part down to never really having had a car thats comfortable or economical at much higher speeds (1.0 Micra, 1.7 N/A Diesel Corsa, 1.0 Polo and 1.0 205), but also because I find driving much faster and battling it out with the Audis and BMWs incredibly stressful, and on the motorway that stress is never rewarded with an engaging drive, so I rarely go over 65

That said, when I've been in a hurry, even in little 4 speed 1 litres, 80mph is generally easy and safe and yes, it requires more concentration, so I can see why there is call to change it.

I get where you are coming from but the point I made regarding braking efficiency still stands.
Ive been driving for 33 years this year and I can tell you with confidence that people were tailgating back in 1982 and every year since!
The standard of motorway driving hasn't improved or deteriorated but cars have improved multiple fold and that's the point.
As quick as my Lotus is, as good are the all round disc brakes are ( not that great TBH) my 2014 Skoda will get from 100MPH to a standstill quicker than said Lotus would get to a stop from 70MPH.
In context, shunts still happen on motorways but you have a better chance of avoiding one now if you slam on the brakes in a modern than you would if you were driving a MK3 Cortina.
Basically, most of us break the speed limits yet motorways are safer than they ever have been.
That's not a coincidence.

You're quite right Rob M, modern cars are way better in the braking and hazard avoidance than when the speed limits were set.

I'm in agreement that a higher limit would be sensible, drop in speeding fine revenue is probably the biggest reason it won't happen

Cars may have got a lot better in terms of brakes systems and ABS etc. but I would question whether a lot of average motorists on the road would be safe driving at higher speeds as after all its them controlling the braking

Personally, if I'm in the B I tend to keep it to 60 in order to keep my hearing/sanity and in the Jag I'll generally keep it below 70 for fuel economy reasons.

Although because the Jag is more modern and refined, I will find myself creeping up on the speed because 70 feels too slow for it

It may well be true that cars are vastly improved from the times when the speed limits were created but the people driving them haven't evolved since the sixties. There's still a limit to the reaction times of the average human brain and body and then you have to multiply that by the number of people sharing the road. Obviously everyone here is an excellent driver (and accusing a man of being bad at driving seems to be tantamount to questioning his entire manhood ;-p) but most people are average skilled, some obviously below average, They have kids in the car, the radio on and other distractions and they see driving as a means to an end, rather than driving for the pleasure. 

The safest road would be one where everyone is traveling at the same speed, with no junctions or changing lanes. When you factor in HGVs (speed restricted), junctions, weather and unpredictable emergencies that's where all the potential accidents happen. 

Personally I don't like motorways, I'm content to bumble along in the left lane at 60ish and only bother overtaking particularly slow trucks and so on.

Yep, that pretty much sums it up.

I tend to drive in the correct lane (lane one - the 'slow' lane) at between 60 and 70, mostly for economy reasons. I find the driving skill in the faster traffic is distinctly lacking, people in the wrong lanes, with some sort of entitlement ('I need to be in front of you','I'm going faster than 70 so I'm staying in the fast lane' etc) or driving too close to each other. I leave plenty of time for my journey and watch the idiots fight it out in the other lanes.

I've recently completed a speed awareness course (yep, even slow old me!) and was particularly struck by the difference speed makes in a motorway accident situation. faced with the same situation (forgive me if this is wrong, it's from memory) a driver faced with a sudden accident/incident in front of them doing 60mph safely stopped, the one doing 70mph hit the (fictional) accident at about 30mph and someone travelling at 100mph was still doing 70mph as it ploughed into the pile-up.