I don't find that argument very persuasive. First, while there are dialect differences I think this argument significantly overstates them - I think the last answer in this Quora discussion sums it up well, saying that it's like the differences in American and British English - significant, but hardly a serious barrier: http://www.quora.com/Korean-language-1/How-different-is-the-...
It's not like North Korea's government just picks random proles and tells them to start writing malware if they want to keep receiving gruel; anyone engaged in cyber-espionage is going to have a very high security clearance and be well educated by North Korean standards. You wouldn't be surprised by the idea of a KGB officer (or FSB these days) that spoke perfect English, would you? Why is the idea that North Korean spies would be fluent in dialect/idiom of their own language so hard to swallow? I would imagine that any North Koreans engaged in cyber espionage/security has spent at least some time infiltrating South Korean social networks, to gather intelligence, disseminate subtle propaganda (as opposed to the chest-beating type put out by the official news agencies) and so forth.
I don't know if the Sony attack was carried out by NK or not, but the idea that it could not have been rests on the notion that North Koreans are incapable of social engineering, acquiring language skills beyond their own, or impersonating anyone else for espionage purposes - a modern version of the trope that Russian spies could be quickly detected by the poor cut of their suits.
It's not like North Korea's government just picks random proles and tells them to start writing malware if they want to keep receiving gruel; anyone engaged in cyber-espionage is going to have a very high security clearance and be well educated by North Korean standards. You wouldn't be surprised by the idea of a KGB officer (or FSB these days) that spoke perfect English, would you? Why is the idea that North Korean spies would be fluent in dialect/idiom of their own language so hard to swallow? I would imagine that any North Koreans engaged in cyber espionage/security has spent at least some time infiltrating South Korean social networks, to gather intelligence, disseminate subtle propaganda (as opposed to the chest-beating type put out by the official news agencies) and so forth.
I don't know if the Sony attack was carried out by NK or not, but the idea that it could not have been rests on the notion that North Koreans are incapable of social engineering, acquiring language skills beyond their own, or impersonating anyone else for espionage purposes - a modern version of the trope that Russian spies could be quickly detected by the poor cut of their suits.