From today's research combined with insight from Tom and Tony, we discover two important things about the relationship between IV and price:1: When the S&P moves small, its implied volatility seems to be relatively independent. We see the true “inverse correlation” between the market and its IV happen when SPX moves greater than 1% either up or down.2: Holding short delta, therefore, provides a hedge when markets sell off big. That is when IV and price exhibit their strongest negative correlation and short premium portfolios are the most exposed.