Reinhart e Rogoff perderam muito tempo com os argumentos errados. Vejam o gráfico:

Brincadeiras à parte, gostei da carta dos autores a Krugman e do post do Hamilton.

Já DeLong argumenta que, se os autores dizem que a idéia geral do artigo não se altera radicalmente por causa dos erros, por outro lado, isso não muda o fato de o argumento ter sido fraco desde o princípio (não que eu concorde com DeLong, mas o ponto é mais do que pertinente):

The third thing to note is how small the correlation is. Suppose that we consider a multiplier of 1.5 and a marginal tax share of 1/3. Suppose the growth-depressing effect lasts for 10 years. Suppose that all of the correlation is causation running from high debt to slower future growth. And suppose that we boost government spending by 2% of GDP this year in the first case. Output this year then goes up by 3% of GDP. Debt goes up by 1% of GDP taking account of higher tax collections. This higher debt then reduces growth by… wait for it… 0.006% points per year. After 10 years GDP is lower than it would otherwise have been by 0.06%. 3% higher GDP this year and slower growth that leads to GDP lower by 0.06% in a decade. And this is supposed to be an argument against expansionary fiscal policy right now?….

Gráfico retirado de Os números (não) mentem.