Originally Posted by faire_jour
The question is whether or not a deaf person can grow up to be successful without ASL, not whether or not ASL is useful. I grew up without German, and I did fine, but if I learn German as an adult it doesn't mean I was incomplete without it.
That comparison doesn't make sense. Where did you grow up in the States that German was important?
Your comparison would make more sense if you grew up... in say Quebec.