Regarding the Public talks being monitored to make certain that the speakers stay with the outline. I think it is a congregational thing. I grew up in a predominately Black congregation in a city, and the majority of speakers we had at the hall were Black brothers. I belive that the congregations during that time were different in the different areas you were in. For example the congregations in the deep south were warm and the talks were more personal and people even spoke up and said 'Amen' in some instances. The singing also was much more choir-like.
Now there were two instances of monitoring of talks etc:
1. My bookstudy conductor gave up his afternoon bookstudy to an older brother in the hall and privately disclosed that it was because he got to excited over the material and strayed sometimes from the information being considered. He simply would smile and say "it is Jehovah's direction and we have to go along with it." He would still read at bookstudy with his booming voice. I think it was his way of getting back at the brothers for having him switch from conductor.
2. The KH also had certain brothers who they did not invite back because they came accross as to much like a Preacher and would go overtime or do their own research. Of course this was nowhere in writing but was discussed as an elder body.