Read down to paragraph 5.

http://www.nytimes.com/2013/04/27/world/europe/eu-is-pressed-to-reconsider-cuts-as-economic-cure.html?hp&_r=0

There were some disputable theoretical elements to what Rogoff, et al did, but the real problem wasn't theoretical at all.

It seems that the wizards at Harvard did their analysis in an Excel spreadsheet and one formula had a serious error in it.

Of particular note is the nature of the error. It wasn't related to some obscure, esoteric math theory...

no.. these geniuses just summed the wrong rows!!!!

I've done some doozers, but it would be hard to top this one.