The problem is a mixture of Mother Nature, the BLM and the MotherF'ckers that they have allowed to haul the salt out of there by the train load for the last 60 years or so. There is not enough salt crust to allow safe racing. It is wet, and the thin crust has lots of mud patches throughout the course. The SCTA was able to find 2 1/4 of raceing surface, takes about 7-8 to support the fast stuff including a couple of bikes that are shooting for 400.
A lot of discussion on Landracing.com