there is such mod and it's presented in the video (but I doubt it shows the trully optimal line)
If someone wanted to add it just in the video he'd have to either apply some complex algorithm to mask the car and several textures that are "over" the green line multiple times during the video, or go through the video frame by frame editing it. Probably both are more time consuming than making this mod, I'd contact the author and ask about the MTA server he played on