I was on a forum last night and a question posed by one person was; Do you think a national speed limit of 55mph should be set, to save gasoline?
Personally I am of the opinion that this is stupid. Depending on the vehicle 55 may not be the optimum driving speed for gas use efficiency. If people want to use more gas that is their prerogative. Might as well tell people to not buy SUV's or Pick-up trucks or even outlaw the sales of them. Driving at a steady pace, don't waste gas idling, don't rapidly accelerate and then brake, and just keeping the cars tires properly inflated would save more gas than forcing people to drive slower.
Other people argue, People who drive fast are unsafe. Guess what the rate of accidents caused by speeding is. According to the Florida Department of Transportation the percentage of accidents actually caused by speeding is very low, 2.2 percent. UK Department for Transport agrees with Florida's report says only two percent of accidents among drivers over 25 are caused by exceeding the speed limit. The Transport Research Lab, funded by the UK government, did a study that showed the number of accidents in the entire UK involving speeding at all was an average 7.14%. Speeding doesn't really matter. Drivers need to be taught to drive well and adjust their speed to road conditions. There are times when exceeding the posted limit is perfectly safe, and times when it is unsafe to go anywhere near speed limit.
Now onto speed cameras. Speed camera's are simply entrapment and do not reduce the number of accidents at all. Accident numbers have increased at some camera locations, because people slow down to not get ticketed and the people behind them hit them because they just hit their brakes for no discernible reason. At least one speed camera in my area has been removed for this reason, accident rate increased not decreased. Speed cameras are not always accurate, Mythbusters has shown that some cameras can be fooled by birds flying by. Some people argue that speed cameras will stop people from racing. Not true, those who want to street race still will, they will find out the locations of the speed cameras and race somewhere else. Speed cameras are also vandalized often attacks with explosives, hitting them with cars, cutting them, shooting at them, etc.
The real cause of accidents is poor driving skills and inadequate training/experience. After that it is distractions like cell phones and navigation systems. The vast majority of accidents are caused by distraction. Cell phones are really dangerous. Studies have shown people who talk while driving are just as dangerous as drunk drivers.