Close, but not quite. Amber is just a safety light, everybody is required to run them in a sanctioning body. Us guys who chase do it for the same safety reasons, so people see us if we end up on the course. The blue light does indicate slow traffic, but slower classes aren't REQUIRED to run them if I recall correctly, but some choose to. For instance when you're running the Baja like Filar did, he chose to run a blue to avoid a trophy truck from running him over haha. If you see an amber light in front of you, you know there's a vehicle up there. If you see a blue light, you know it's a slower vehicle, and it gets you ready to have to dodge something.