That was just a line to keep the proles subservient and waiting.
Huh? The trickle down line comes from comedian Will Rogers who was making a joke about how President Hoover, who was an engineer, was accustomed to water trickling down, but that he didn't realize money trickles up.
It was a line to serve the exact opposite – to tell the 'proles' that the economic plan was fundamentally flawed.