Actually - I really don't know. The few that I can think of, they know ASL because their parents are deaf and everyone does ASL at home. Their parents also have okay English as well (not the best, but good enough). So, I really do not know where they have failed at Education. I know they learned at a lower English level than the rest of peers. This is why I came up with the conclusion that ASL is causing confusion with English because they're totally two different syntax. Now I realize that I am wrong, ASL is not at fault at all. The only thing I can think of is the teachers are not knowledgeable enough about ASL language to translate into written English (this is where Bi Bi approach would have worked well).
It's been a long time, so...
Poor ASL - Yes the few people that I know, yes has poor ASL skills because they only sign in school while at home they talk. Their parents don't know sign language. My mom is one of the few parents that does know sign. So, I see a lot of students cannot really sign in ASL, myself for one. Although I can understand ASL and sign in ASL "signs", but I cannot get rid of the English thoughts that's in my head. (See my next post about this....)
There is Early Childhood Intervention program at my school. The kids are taught both oral and sign. Simple signs and simple spoken language. It is during IEP meetings to see what will benefit the child the most. There are a few that cannot speak well (either due to poor listening skills, poor auditory skills, or just doesn't want to), and they will not be forced to take speech classes. Those who does speak well gets speech classes. It's NOT AVT, but similar...teaches how to lipread, how to say words properly such as spelling words or sentences, idioms, etc etc. I learned how to say ceiling. Stuff like that.
Nowadays, there's a huge influx of CI children and when I went to visit there last, many do NOT sign. They were jabbing to me and I had no clue what they said.
This is why I thought the school I went to has such a huge diverse of education between the students. Not all are successful.
There are a lot of students who also have other disabilities on top of deafness.