Small group is not a marketing detail. It is part of the teaching method.
When the class is capped, Teacher Au can ask every student to show working, notice when someone is guessing, and correct a method gap before it hardens. In a large class, a quiet confused student can sit unnoticed for months. Here they cannot.
- Students are expected to participate.
- Questions can be checked through working, not just final answers.
- Quiet confusion is easier to notice in a smaller group.

