“A la carte” group lessons of 1h30 with a specific topic are excellent for meeting and discovering a teacher. This gives insight into their style of teaching, methodology, philosophy, favorite teaching topics, etc.
It is a formula very well suited for festivals where each student picks what they want to discover and with whom they want to learn.
On the other hand, it is too short for in depth work which would requires more than 1h30.. It is also limits the exchange between teacher and each student.