Think about it. There were lots of sharp recessions both before and after the Great Depression. Why is it that the one that FDR tried "bold persistent experimentation" during was the one that morphed from a sharp recession into the Great Despression? Why would we ever want to copy what FDR did while he presided for his entire 12 years over a dismal economy? If 12 years wasn't enough to turn it around... maybe you should try something different. Stop the bold governmental experimentation and let market forces steer the recovery and you would be back on your feet in 2-3 years max. Here's Reason TV's video on the subject:
For a refresher course on Keynesian economics, also watch this video from CATO's Daniel Mitchell.