I don't think he has any responsibility to non-signers, I don't think he has to do captions.
I think there are two reasons to make communication as clear as possible.
One is that you have a responsibility to your audience, or they need to understand your message, or some authority thinks this is true, etc.
The other is that *you* need them to understand your message, or it's important to you that they do.
My arguments for captioning this video involve the second reason, not the first, so FCC laws don't feel so relevant to me here.
If I'm sitting in a coffee shop with a few friends who sign, but everyone else in the place probably doesn't, how do I communicate? If I want to say "I think I'm going to get another coffee. I'll be right back." I'll probably sign that. We want to sign, we came to sign, and I have no need for everyone else to know that I want more coffee. But if the place is really crowded and one of my friends is having a medical emergency and we need to get him out to the street (lets say a claustrophobic panic attack and he can't breathe, I don't know) then I'm probably going to be as clear as I can, stand up and yell "Hey, can everyone back up? Clear a path? My friend is sick and needs to get to the door!" (And also sign if my friends are deaf.)
Point being, I'm not doing this for the benefit of the non-signers. I don't feel any sense of responsibility to them. I make my message accessible to them because it's important *to me* that they understand me. I would think that this video would fall into that category as well. We *want* everyone to understand what a difference it makes to go to a deaf school. Because we want them to support efforts to keep deaf schools alive.
No?
