Quote Originally Posted by Throbert McGee View Post
True... for example, I would bet money that if you showed him a photograph of a bird from the genus Passer ...



...and asked him Что это такое?, he would answer Это маленькая птица ("It's a small bird") or something close to that, whereas most Russian children over the age of five or six would answer Это воробей ("It's a sparrow").

Or, if you asked him how to say "Those people are very wealthy" in Russian, he might be able to provide a direct literal translation like Эти люди очень богатые, but it would never occur to him to say У них всё есть, кроме птичьего молока, ("They've got everything but bird milk") because he was too busy learning Hebrew, Catalan, Afrikaans, etc., to study Russian in more depth and learn some common proverbs and figures of speech.

Which is to say that "fluency" can be defined in different ways, and the BBC video shows that he has an impressive ability to master different accents and perhaps also an excellent memory for rehearsed phrases, but he's not actually demonstrating an ability to converse fluently in all those different languages. (Maybe he can, but the video doesn't prove this.)
I think you're defining "fluent" so narrowly you're in danger of rendering it meaningless. If you can talk confidently and readily on a range of subjects without getting stuck then you're fluent, in my view. I'd actually argue that peppering his speech with idiom and proverbs would be a far greater demonstration of "an excellent memory for rehearsed phrases" than talking freely, albeit in more simple language. I tend to avoid using proverbs in Russian even when I know them and can use them correctly because what commonly happens when I do drop one into conversation is that the listener interrupts me to smile and congratulate me on my correct usage of Russian idiom, and the conversation is immediately derailed. I'm also conscious that as an English speaker I always find something amusing and even absurd when I hear foreigners using English idiom, even when they're using it absolutely correctly and their English is otherwise perfect.

As for the воробей, I would answer "it's a small bird" in English, because I don't know one wild bird from another. Does that mean I'm not fluent in English?