I'm not sure I agree with 15,000 hours. I started a job in French 4 years ago, I could hardly stammer out a sentence with my one university french course, now I

I'm not sure I agree with 15,000 hours. I started a job in French 4 years ago, I could hardly stammer out a sentence with my one university french course, now I'm quite apt. A quick calculation of work hours puts me around 7000, much of that working alone at the computer. So maybe 2500 hours of conversation got me to a high level of fluency.