It is not an overwhelming factor but if for example you were to go from 20mph to 10mph you would see an effect. Overrall lower speed limits (when streets are d

It is not an overwhelming factor but if for example you were to go from 20mph to 10mph you would see an effect. Overrall lower speed limits (when streets are designed to take advantage of them) have a lot of benefits, this is in the category of minor drawbacks.