the fact that he was doing it wrong may invalidate his claim that it's nigh impossible for adults to learn a new language (from what I remember, people are also

the fact that he was doing it wrong may invalidate his claim that it's nigh impossible for adults to learn a new language (from what I remember, people are also more sceptical about some "language window" closing off one you hit 5 or so), but his other point about the attempt improving his general mental abilities is surely still valid.