He may have been short prior, but he went for the juguler after the open. My research is that was his plan all along, he was taking advantage of the portfolio insurance that he knew would inevitably push the market down more.
Bonds soared on the day of the crash, but gold did not benefit much on that day. The british government was in the process of privatising BP and had placed, via the bank of England, a very large number of shares to be sold with several NY investment banks. I know Salomen and Goldman were both involved, but i don't know who else. Some blamed this flood of BP stock into the sell side of the market as a precipitating factor, but i don't think that had anything to do with it.