Well, having now crashed at Edwina's I think I know what it is. I'm talking about exiting Edwinas here. Going in, I had no problems other than the usual chatter from the rear.
The road there is pockmarked with hundreds of holes from bikes going down. Which leads to a rough surface and holes just the right size to swallow a contact patch
So the more peopel that fall off the worse the surface gets and so the circle continues.
Now, having the track cleaned with detergent after Western's off made a huge difference so I'd presume the track there has seen a lot of Oil from all of these crashes and it was percolating to the surface with the rain in the last week/month/season. So, the oil makes people crash which adds oil. Another circle!.
I couldn't belive how Sh*te the track surface was! There are back roads in yorkshire that are 10 times better! There were gouges, holes, poor jointing, polyfilla and really poor quality tarmac.
The tracks is most definitely ready for a resurface!
C