It sort of doesn't work when the rich hoards cash like in this case. So far, there is no solid evidence that cutting taxes on the ultra rich does anything to stimulate the economy, especially employment growth (who knows- it might happen given the conditions fall into place). Since we have free trade and deficit spending has screwed the US even more, the theory in this case will definitely not work unless the rich stops hoarding cash.
Sound and constant fiscal and monetary policies help the economy grow. Stop changing laws like a person changing clothes and limiting dumb lawsuits will help the economy grow.