Back in the early '70's there were only 3 speed ratings for radial tyres (commonly) - and cross-plys were the 'standard' on many cars from the manufacturers, and they had their own set of ratings which I won't go into, as it's not relevant.
Basically, they were either SR, VR or ZR tyres - SR were good for up to 113mph, VR up to 130mph, and ZR for over 130mph.
At the time, the Con & Use Regs (which have since changed, but the basic thought [& Legality] process remains the same) dictated that a vehicle can only get Type Approval, and therefore be good to use on a UK road, if it was fitted with tyres which were suitable for it.
This included a weight index for a full capacity, and a speed rating suitable for that cars' maximum speed (irrellevant of any limits in the destination market).
The Scimitar is an awkward car to use as a reference point, as the various models produced 'maximum speeds' of 117mph, or 110mph, depending on the engine used - the straight 6 2.6 engine gave 117mph, but when the 2.5 V6 was fitted it dropped to 110mph - this enabled the factory to sell them cheaper as (amongst other things) they could get away with cheaper tyres (VR were expensive in those days)....
... once Reliant had built up a good reputation and customer base, they increased the engine capacity to 3.0, and the top speed was back to 118mph, and VR tyres were again fitted.
Many owners (not just of Scimitars, but loads of other cars of the time) still used the cheaper SR tyres as a Service Replacement on the 'faster' cars as they didn't personally go at max speed - but should they ever come to sell the car, it would have been illegal (and an arguable case in event of an insurance claim).
At that time, remould tyres were also in their infancy (for Radials, although they had been common on X-Ply for years) - and they were notorious for falling apart at speed as heat caused the tread area to peel away from the carcass - this no longer applies as they are now made in a totally different way, not just with new tread stuck onto the outside of a worn tyre!
Anyway, as time went on, other 'Speed Ratings' were introduced - firstly HR, then WR then every other letter of the alphabet!! - each with their own Speed capability.....
...Then the "R" part of the notation was dropped, as it only ever showed the tyre to be a Radial in the days when there were other options.
(I've totally ignored Bias-Belted tyres in this post as they were never fitted in the UK - and appologise to any of our Colonial Cousins who think of them as a 'Standard' tire
)The ratings are NOT the speed that they can be driven at (surprisingly!), but the speed that they can be driven at for 60 minutes, with 125% of Maximum Weight applied, and 5 minutes with 200% of Maximum Weight - as long as they remain good, then they pass the test and achieve the appropriate Rating - this was to simulate the cornering forces likely to be encountered.
[The system may well have changed again in the meantime, but no doubt it ain't gonna be any simpler!].
As such, it was technically illegal to use a Scimiter with SR tyres - but with the weights involved, at UK driving speed, would be unlikely to ever cause a problem.... however, I fully agree that the remoulds (in those days) would make the driver the "'king idiot" you mention
Moving on to the Elan..... were now into the late '80s/early '90s and tyre technology has improved (along with availability), but the UK Law remains the same - it must be sold with tyres suitable for its maximum speed....
...hence the different speed ratings for tyres on an NA to those on an SE (and how many of you are now looking at the Owners Handbook and thinking, "I never knew they were different!"
)Again, at that time, we only had the 3 common choices of SR, VR and ZR - so the SE HAD to have ZR tyres, whilst the NA could get away with VR.
.... and then it got complicated, as most mainstream car manufacturers got onto the same bandwagon of producing cars which went faster.....
....but they had to remain price competetive....
and so, other tyre ratings were developed - most notably HR which fit nicely between SR and VR, with a maximum speed of 125mph - crucially, even though it is only a 5mph difference, the cost to produce them is a hell of a lot less than a VR tyre - and so it became the tyre of choice for many manufacturers - and even in those days, many cars left the factory with a top speed of under the magic 125mph just to get the cheaper tyres fitted, and give them the edge over the competion - after all, 1mph of speed isn't noticable to the customer, but a £400 saving is!!!
Okay then, so back to the main point of my contention - what do we need to fit to our Elans NOW......
To remain "fully legal" we need to have a speed rating of at least "W" (and lets be honest, how many tyres can you find for sale at the size we need in a 'low speed rating' - they just aren't made/sold in the EU, although some other markets *may* have them - hence always check imported tyres!!!)
And this also make perfect sense - they are designed for the speed of the car - and with so many 'chipped' cars out there, even more so.
Can we legally use a tyre with a "V" rating??? - yes and no - yes, you can buy and fit them - no, you can't sell a car with them fitted.
What is the safety implication? - TBH, it'll make little difference - with the weight of the Elan, the tyre shouldn't get 'over limit' even after flat-out driving down the road all day.
Is it 'worth while'? - to me, no - but to you, it may be. Actually there are actually quite a few "Track day" tyres availlable in this sizing, and I'd rather use a Yokohama A048 on an Elan than a part-worn ZR tyre of any make
How about "H" rated tyres?......
Again, as long as you drive within the limits of the tyre, you can fit them, but not sell them.
S?
You won't find many - and those that you can buy are clearly marketed as a 'Winter' tyre.
So, what are we left with?
Do we need a "Z" rated tyre - NO
We need at least a "W" rated tyre - and these are easily available now, but were not when the Handbook was written.
So, I don't say that youre wrong, Phill to use a "Z" rated tyre (and that's what I've got on mine!) - but to call someone a "king idiot" for using a perfectly acceptable "W" rated tyre isn't (IMHO) appropriate..... and the jury is out on "V" rated ones....
..... there again, if you were meaning something totally out of the ball park, I'd agree with you. (even though you can buy/fit Winter tyres and drive at speeds up to 113 mph quite legally)
) in respect of what can be safely and legally used.
All of them had V rated tyres on - without exception!
)......
They originally came out as VR & HR and the SR only appeared when Cinturatos were being marketed to 'boy racers' in small saloons ...
) - it was picked apart by Sgt Colin Hills, and I ended up with a list of things to do before I was allowed back the next week 
Chantmarle, down in Dorset - I joined a proper Police Force, not the Met!!! (Only joking - but every copper reckons theirs is the best training centre.)
My only suggesstion is that by it's very nature, Wikipedia can be added to or edited by anyone - and the start line refers to tires, not tyres, so may have been originally written by an American - back in the day, they had few radial ty(i)res over the pond, and nowt went very fast!
