I know some people who cannot understand or will misunderstand what is being said in English because of the ASL structure that they follow. I've tutored some students who claim that NTID isn't following Deaf Culture because their English assignments are "too hard" or follow English when they should follow ASL. That's the kind of people I'm talking about.
I have some friends who can sign ASL, but they can also sign SEE and PSE. However, other deaf people will look at these as not being part of Deaf Culture because they know more than ASL and that doesn't fit the profile of a Deaf person.
That's strange, disowning someone from a culture for knowing unapproved material. What about interpreters who have to know all of those?
This reminds me of a guy who was in my high school. When I was staying after school with my mom and sister there, that guy was there for some reason and saw me signing. My sister told me that he said sign language wasn't real.