I've been puzzling about this for years. It feels different, but what is it exactly? On one level, there's knowing others are going to hear it in a group, which seems to set up a situation where I won't come anywhere near certain topics--too embarrassing or whatever. On the other hand, sometimes a group has made me a more responsible listener to what I write. My level of anxiety has always been greater in a group, but it seems that I have sometimes done a better job of listening to what I hear when I'm in a group. It will be received by others, so therefore I'm more likely to receive it? Alone, I'm freer to get into anything, get down anything that comes, but the one who listens has often been very hard to conjure up. I'm becoming a somewhat better 'audience' to what I hear when I'm alone, and it occurs to me now that the periodic group experiences are one of the things that help that along.
Thanks for asking Toby--getting me to think that through.