I know what you mean. Its a lot easier to talk one on one with someone on a subject you know nothing about, that way you have a better chance of getting away with it. ;)
It is, mainly because I have less problem speaking in front of a large group if I'm speaking about something I really know and love. I'm teaching my passion here. I couldn't imagine giving a "sales pitch" for something that I don't give a rat's ass about.
Stage fright is only an issue if a person's worried about others' judgments. It's an ego thing. I was a teacher, part-time, for about 20 years -- so speaking in public for me was about finding the best ways to share information. Largest group I addressed was about 400 at the Adelaide Arts Festival. The trick is to focus the mind on what one is saying and how one is saying it. The awareness of the audience is general - roughly who they are, their interests and their level of prior understanding of the topic.
This post was edited by Benedict Arnold at January 9, 2018 10:31 AM MST
I hate it. I have spoken in front of groups, formally and informally, both for work and in the town hall. In those situations I was knowledgeable (and sometimes passionate) about the subject matter. When what I am talking about is of import to me and to the audience, I find it makes a huge difference. My first time speaking in public (after successfully avoiding every single speech in HS Oral Communications class!) was in a special town hall meeting that had to be rescheduled and relocated due to the fact that in excess of 500 people attended. My face turned red, my voice shook, my hands shook...but I survived. :)
This post was edited by Bozette at January 11, 2018 3:54 AM MST
I was standing near the front in a crowded elevator one time and I managed to squeak 'excuse me' in front of all those people when it was my floor to get off.
~ 
Randy D 