Suppose your city has a stretch of road between two traffic lights that, if you leave traffic light #1 and accelerate normally up to 40 units, will force you to stop at light #2 (lest you commit a traffic violation of running the light), whereas if you accelerate normally up to 25 units between the two lights, you will find that the second light has changed before you you reach it (i.e. giving you the right-of-way) and without your needing to slow down or stop beforehand, plus allowing you to pass those who are stopped at the light in the lane next to yours because they accelerated too quickly to to to high a speed after the first light and were made to stop due to reaching light #2 earlier than you.