If the green line is kegetys ghost car mod, then its not just a fat green line, it shows where you brake and where you start to hit the throttle. It also does NOT show the racing line, but the line you took when the fastest lap was recorded.
I used this when trying to beat my pb's and was amazed how much later I could brake, how sooner I could get on the gas and by getting a much better line through the corners.
Arcadey definitely, but as an offline tool to learn the tracks, usefull IMO.
Andrew
Edit:
What I meant to say was whether the green line was based on kegetys ghost car mod. Scawen may have some other info going on in there......