Old school rules! like it! silent time is definitely important but if it's all the time then the students are always trapped with only their capacity for reason to figure stuff out. The teacher can be an imposing figure (especially one who commands silence). Classmates can be more approachable and conversation with them is often more of an even playing field. Plus many more conversations can happen at once.
Silence is golden, but I'm not sure it should be the norm..