Perhaps the publisher is using the pre-orders to calculate the size of the print run. This is an expensive book aimed at a small niche market. In order to maximize their profit, the publisher doesn't want to print too few, but nor do they want to have copies in inventory for years. Since I've been looking for a copy, I've seen several sell in the $500-$800 range (while none of the $1,000+ copies have sold), so they may have printed too few copies of the 2nd edition.