I was interning at this place and the team lead would come and ask the interns what they were doing (at least once a week) and ask really in depth questions. It was extremely nerve wracking because this was the only interaction I had with him and he kept a air of "hard ass" around him. Every few weekly meetings he'd ask the interns for more information and put us on the spot.
It sucked. BUT by the end of the internship I think we all felt a lot more confident speaking and defending our work. So I guess his plan worked, and honestly I'm happy to have had that experience. I think it made me not only a better worker, but a better employee. At the end of the day, we all are in sales in some form. So I do not like the idea of someone else giving the talk, because that's not the person that gets the training from it.
What I'm trying to say is that talks like these really should be used to help your team members with anxiety. A bit of low risk exposure therapy. Speaking is a skill and it is an extremely useful one to every person at every stage in their career. You are supposed to train your employees and sometimes that means making them a little uncomfortable.