perhaps its LFs weird mapping again. maybe it uses track skidmarks somewhere on track, but the other "main" on other parts as we see it with other dds files aswell on tracks. i havent looked into so much that i can actually answer that. atleast not yet. so just a thought.
These are just aesthetic skidmarks. For example, if you closely look at Blackwood Turn 1 you'll see that these "skidmarks" on some spots are floating or clipping. Same thing happens with Westhill. (BLWskid_ALP and WSTskid_ALP are the respective files).