My late brother-in-law was a traffic officer here in Wiltshire, and my wife's ex-hubby was also a copper.
Although both were careful not to endorse routine motorway speeding, they both said independently of each other that traffic officers are not especially interested in speed per se, but take a dim view of speed combined with any of the following:-
Poor road conditions / traffic conditions / visibility;
Apparent inattention to surrounding traffic conditions, highlighted by lack of lane discipline, lack of indication, lack of awareness of following traffic;
Any distraction consuming the drivers attention, like mobile phones, putting on make-up, turning to scream at kids in the back, etc;
tail-gating;
Under-taking;
any attempts to intimidate other drivers to move over.
None of the above means that a motorist behaving sensibly at 85 mph on the motorway won't get pulled, but most traffic officers are motoring / car enthusiasts (thats why the majority of them do the job), and only want to catch and deter the idiots.
The above absolutely chimes with my own personal experience - I frequently travel at 90 mph and occasionally (and for short distances) more on motorways, but I drive in accordance with the list of 'dont's' above. I have NEVER been stopped for speed on a motorway.
Why not just drive at the posted limit T?
That's a perfectly fair question, Zulu.
Here's my self-justification, which isn't intended to be bullet-proof, merely honest like my original post....
First of all, almost nobody in a modern-ish car drives at the posted limit on a motorway, so I'd suggest that those that do may be posing a more significant hazard than those keeping up with the general velocity on such roads, i.e 80-85 mph.
Secondly, I find I'm less alert in the sense of being less aware of whats going on around me when travelling at or near 70ish on motorways. I ease off mentally in the same degree that I ease off the accelerator. I know, that's my failing, but I'm super-aware when travelling quicker.
Thirdly, as Albs says, why have a large-engined motor designed to chew up motorway miles in comfort if you're never gong to extend it a little now and again?
If we all accept that motorways are the UK's safest roads, with all traffic heading in the same direction, without junctions or traffic lights, without pedestrians, without cyclists, then surely the motorway is the place for that speed (notwithstanding the caveats in my original post).
I'm not saying I'm right, but this is how it is for me. Am I attempting to justifying the unjustifiable? No. Really, I'm not - this is just an honest answer to an honest question.