Clearly on the wrong side of the Laffer

The inflection point of the Laffer curve is under discussion at Ezra Klein's blog. It unintentionally reminds me that FDR once seriously proposed a 99.5 percent marginal income tax rate, proving once in for all that such exercises are important:

As pointed out earlier in this essay, Herbert Hoover's own version of a "New Deal" had hiked the top marginal income tax rate from 24 to 63 percent in 1932. But he was a piker compared to his tax-happy successor. Under Roosevelt, the top rate was raised at first to 79 percent and then later to 90 percent. Economic historian Burton Folsom notes that in 1941 Roosevelt even proposed a whopping 99.5-percent marginal rate on all incomes over $100,000. "Why not?" he said when an advisor questioned the idea.