Ironies abound indeed. Strange how the most doctrinaire speed control advocates are also the ones who believe in implementing the will of the majority and ensuring democratic representation. If you take a speed gun survey of a typical motorway outside of peak times, you'll find that these same majorities are voting with their feet and disobeying speed limits they know to be completely arbitrary.
I'll continue to hang my hat on the engineering approach of using the 85th percentile speed as the "recommended" operating speed for a given stretch of road, thereby minimizing speed differentials and accident exposure. Enforcement should be only directed at "imminent threats" to the safety and property of other motorists (i.e. blotto drunks and completely reckless maniacs)

As a slight aside, will journalists ever grasp the use of rates in measuring relative exposure to risk? Otherwise statistics such as these are useless:
In 1966, the worst year for accidents, there were 7,900 deaths, including 3,153 pedestrians. Last year, there were around 3,100 fatalities. This is cited as a success for the speed cameras.
...and the increase in vehicle miles travelled over the same time period was?

To counter the argument of money-grubbing, why don't they dispense with the fines altogether and just let people lose their licences by blowing through too many cameras? Give someone one free warning photo, then start taking points. One idiotic stretch up the A1 could cost you your licence, so the onus is back on the motorist to behave, as it ever was. An attraction here would be that councils would not anticipate revenue and thus would really have to limit the placement to sites where it really would be cost-effective to have them (ie, accident hot-spots).

It's a bit of a conundrum - they probably don't want to nail everyone who goes through, just those who do it in an egregious fashion, but they have to set the limit and the tolerance so people know what the rules are.

There is a slight flaw in your reasoning. Brakes, along with handling, acceleration and road holding on modern vehicles have indeed improved dramatically in the past few decades - people, however have not evolved as quickly. Our reaction times are limited. Given that a safe speed is going to be dictated by this along with driving conditions (road surface, traffic density, roadside hazards etc) any speed restriction will, of necessity be a compromise. Therefore, the 30mph urban limit is probably about right. There are, however, times when it is not - sometimes due to the prevailing conditions it should be much lower. There are also places where roads could support much greater speeds where they are currently restricted to the 60 or 70mph national limits.

The ideal arrangement would be variable, risk based speed limits that reflected the conditions - that, along with adequate driver education that gives each individual an understanding of personal limits (just because you can do 100mph+ on an autobahn doesn't mean that you should).

No, too much like common sense and why do that when political correctness is so much fun (and profitable)?

There is a slight flaw in your reasoning. Brakes, along with handling, acceleration and road holding on modern vehicles have indeed improved dramatically in the past few decades - people, however have not evolved as quickly. Our reaction times are limited. Given that a safe speed is going to be dictated by this along with driving conditions (road surface, traffic density, roadside hazards etc) any speed restriction will, of necessity be a compromise. Therefore, the 30mph urban limit is probably about right. There are, however, times when it is not - sometimes due to the prevailing conditions it should be much lower. There are also places where roads could support much greater speeds where they are currently restricted to the 60 or 70mph national limits.

The ideal arrangement would be variable, risk based speed limits that reflected the conditions - that, along with adequate driver education that gives each individual an understanding of personal limits (just because you can do 100mph+ on an autobahn doesn't mean that you should).

No, too much like common sense and why do that when political correctness is so much fun (and profitable)?

How did that happen???????

Well I think the Tories have it right by suggesting that town speed limits are cut to 20mph and motorways etc are increased :)

Well, what I personally think is ridiculous is that the Scottish Executive could decide to spend millions (if not billions) building a fancy new motorway from Thurso to Dumfries, but it couldn't actually decide to put an 80 mph speed limit on it.

That is one of the crazy anomalies of devolution which would likely not exist if we had a proper federal structure in the UK.

Sorry, I have digressed. :-)

Perhaps the whole of the UK should adopt Scottish law and systems - rule from Edinburgh anyone? ;-)