I don't think the top of a bubble burst, a once in who knows how many decades event, and the resulting turn up after the sell-off, is a great example of how well they work. Look past the last 4 years, take the 10 years before that for instance, and see how many crosses up and down there were and how easy they were to trade, or use to say get in or out. How many of those death crosses down were within months of major bull moves starting? End of '90, '94, and '98 are great examples of how "great" they worked. In 90/91, if you got out with the cross down and got in on the cross up, you would have lost 12%.