I'm part of a National Stuttering Association group and the majority of our members say they stutter less in meetings because it's safe and there is less pressure/anxiety related to speaking. However, one guy did share last meeting that being in a room full of other people who stutter seems to make him stutter more. There was also a person last meeting who said he has no problem speaking in front of hundreds of people (!!!), but that he'll stutter more with people who already know he stutters. So, it just seems to vary by person!