My wife is a native French speaker, and she's always spoken French to the kids. Unlike the author of this story, I've never really felt like I was getting left behind. Before the kids were born, I spent a while studying an Assimil course (a fine course, from a French publisher, for people who like to learn mostly through osmosis with some notes). Afterwards, I plowed my way through 450 pages of a French non-fiction b…
> Given the right environment, the brain seems to adapt. In high school, I had a German immigrant, fresh out of college as an instructor. The moment one stepped into that classroom to the moment one stepped out, nothing but German. Hell, it didn't stop there. If you tried to talk to him at all, in or out of the classroom, he wouldn't acknowledge you unless you spoke to him in German, and he would only speak German to…
I think once you're somewhat proficient in the language, this is true.
I'm currently taking Spanish courses in uni, and my professor is from Cuba. She's the sweetest lady, but has a tendency to ramble off in Spanish. About 50-60% of the time I can (vaguely) follow her, but the rest of the time I'm just hopelessly lost. And judging by the silence the rest of the class has a tendency for, I'm not alone.
Anyway, I'm certainly not trying to counteract your point, just to say that there are steps up to 100% immersion that I feel are necessary.