Originally Posted by
DrIsotope
Slowing down to any speed above walking in order to make the light without actually stopping, will be faster than speeding up to the intersection and stopping abruptly. Nothing consumes more time than accelerating from a standstill.
Not true. Take for example a 30 seconds red light and going 35 km/h. To gradually (and linearly to simplify the maths) slow down to 5 km/h at the turn of the green light, then 5 seconds to go back to your 35 km/h from the 5 km/h, your average speed would be 20 km/h. If on the other hand you stay at 35 km/h until the last 5 seconds then stop (moving speed also stops counting) then go from 0 km/h to 35 km/h in 7 seconds, your average moving speed would be 29,3 km/h.