It's the difference between learning enough to be conversational in a spoken language and learning enough to write a novel in it. Maybe the people who think they can do it in a few months have never written a novel in any language?
The people who think they can learn a new language in a few month, indeed, might never write a novel, but they are out there writing crappy code I'll probably have to maintain on day. They're also getting paid well I might add.
