Althought I agree with you that it’s an important concept “need to sell” to consider, several other factors override this in San Diego. First, the amount the prices and rate of sale fluctuates monthly in San Diego is a truly significant factor. The average purchase price for the county was down $15,000 last month. You NEVER see that high of a fluctuation value anywhere else in the country unless it’s the start of a recession. What this translate to is that even a motivated seller (as long as they are informed and understand the market) is much more willing to hang on to their property for several more months because when the buyer’s market does turn (as it always has) they can sell for much more than a panicked seller.
There are some great articles and insights on seasonal fluctuations in the rate of sale after a home hits the market and list price vs. closing price in specific areas of San Diego (Rancho Santa Fe and Oceanside have by far the highest percentage shifts) at: http://www.HomeGuideSanDiego.com