In all honesty the 80mph will just mean people cruise at 90mph.
People who are screaming at their kids in the back of the car, while applying lippy and updating their facebook status on their iphone while driving along.........
The only way it will boost economy is because the cars will be burning more fuel so lining the government pockets with the tax on fuel!
Lower the limit to 60, save the planet and relax! It's the way forward!