For the benches slopes (in fact they are skew planes at two angles) I already gave you my opinion.Quote
"I think I understand. But this still doesn't seem to address the apparent non-horizontal slope of those "benches" with the cross striations, it doesn't address the apparent lack of wider tracks on curves to accommodate the wheel radius, it doesn't address why some tracks on horizontal ground show erosion between them while others do not, and it doesn't address the sidewall grinding that would occur on wheels that supported a heavy load along deep ruts in bedrock."
For the curves radius, they seem to have been designed to avoid sidewall griding for a given wheel diameter (I couldn't measure curves radius, and neolithic wheel diameter can only be roughly estimated, very sorry), please have a look at this nice curve at Naxxar (not personnaly visited, sorry) :
When a track became too deep, another was created (my opinion, just my opinion, not to convince you, thank you)