Well, Jim, if this is the case then, I guess that the only way to somewhat change it is to try some form of post processing, like SweetFX (blur effect or reduce sharpness). The problem is that this will in turn be applied over *all* the image, not only the track, and the results may be "less than optimal".
The "correct way" (Alex can confirm this) would be to apply different shaders or textures to the road - but this requires changing the track content - not to mention proper authorization, dealing with possible mp mismatches, and so. Unfortunately, I can't help because this is way off my skills.
Cheers.