That FDR lengthened the depression through really stupid actions is a matter of historical economical fact.

http://en.wikipedia.org/wiki/New_Dea...the_Depression

Prolonged/worsened the Depression
A number of economists believe the New Deal delayed economic recovery.[52] A 1995 survey of economic historians asked whether "Taken as a whole, government policies of the New Deal served to lengthen and deepen the Great Depression." Of those in economics departments 27% agreed, 22% agreed 'with provisos' (what provisos the survey does not state) and 51% disagreed. Of those in history departments, only 27% agreed and 73% disagreed.

A matter of historical fact for the economists you cited perhaps but its not everyone else's historical 'fact'. There is no wde ranging agreement on the matter and according to these figurers a higher percentage don't think FDR's policys served to lengthen and deepen the great depression. With the figures in even higher disagreement for historians probably because they look at the comparison with other allied countries who were determined to stick with smith's policys and had to wait for rearmement for WW2 before they're recovery began whereas US started recovering sooner...