Ben Bernanke and Harold James, in a paper called "The Gold Standard, Deflation, and Financial Crisis in the Great Depression: An International Comparison" published in 1991 (NBER working paper version here), noted that 13 other countries besides the U.K. had decided to abandon their currencies' gold parity in 1931. Bernanke and James' data for the average growth rate of industrial production for these countries (plotted in the top panel above) was positive in every year from 1932 on. Countries that stayed on gold, by contrast, experienced an average output decline of 15% in 1932. The U.S. abandoned gold in 1933, after which its dramatic recovery immediately began. The same happened after Italy dropped the gold standard in 1934, and for Belgium when it went off in 1935. On the other hand, the three countries that stuck with gold through 1936 (France, Netherlands, and Poland) saw a 6% drop in industrial production in 1935, while the rest of the world was experiencing solid growth.
A gold standard only works when everybody believes in the overall fiscal and monetary responsibility of the major world governments and the relative price of gold is fairly stable. And yet a lack of such faith was the precise reason the world returned to gold in the late 1920's and the reason many argue for a return to gold today. Saying you're on a gold standard does not suddenly make you credible. But it does set you up for some ferocious problems if people still doubt whether you've set your house in order.