Yesterday evening, a friend and I went to a dinner meeting for deaf people. A few people there were training to be interpreters, and a few were friends, but most were deaf. It was a very interesting experience.
In most dinner meetings, conversational range is limited and the conversation is communal. You can only talk to people close to you, and everyone nearby will hear you and be part of the discussion. But deaf people always communicate by line of sight, either with cued speech or sign language. This means that they have no trouble at all holding a conversation with someone on the other end of the table.* Several times during the night I noticed that several different simultaneous conversations were taking place between people far apart from each other. This could never happen with sound-based speech.
On the other hand, conversation among deaf people tends to be binary. It is very hard to read the lips or signs of two people simultaneously, or even to notice that someone else wants to speak. Interrupting someone or jumping into the conversation requires a bit of effort, so the conversations tend to have only two people talking back and forth. Sometimes someone else will be watching both of them.
If you want to get someone's attention, you have to either flap your hands at them when they are looking in your direction, or poke them, or poke someone else at pass along a message. (It is considered very rude to throw something at deaf people to get their attention.)
All of this means that conversation and group dynamics were very different than anything I have seen before. I get the feeling that there was much more actual communication than there would have been in a group of hearing people. Deaf people communicating never generates any 'noise pollution' so there is no limit to the number of simultaneous conversations. In theory, fully half of the people at the table can be talking at once without interfering with each other, and you could talk with anyone at the table and not just people close to you.
I also got a taste of what it must feel like to be deaf in a world of hearing people. None of them made any sounds when talking. Often they would move their mouths, so that the others could lipread them to aid understanding, but they did not bother to put any stress on their throats or vocal cords by making sounds. So I was at a table full of people chattering away happily, making no sound at all, and I could not understand any of it.
I also noticed that nobody had a pen and pad of paper handy. They ordered either by talking or pointing at a menu. If I was deaf or had any other kind of communication handicap, I would carry paper with me at all times and use that as my primary method of communication. I would write things down and ask others to write in response. But nobody else seems to do that.
In fact, sometimes I think that the world would be a better place if everyone did this all the time. But then, I am a bit odd in liking the precision of the written word rather than the vagueness and messiness of speech or gestures.
*They can also talk to someone on the other end of the room, or even, as I saw, through a window. If they can see each other well enough to see hand shapes, they can talk just as well as if you were right next to each other.