Misconception 1 - McKinsey has only interviewer-led cases. Actually, McKinsey has both types of cases. Managers will mostly give you interviewer-led cases while the partners are too lazy for that and will mostly let you drive the case
Misconception 2 - Interviewer - led cases are different. It's exactly the same cases. They are just a bit shorter and the key parts of the case are clearly structured:
- Getting the case and asking clarifying questions
- Structuring and digging deeper into a certain part of the structure
- Question on creativity
The prep process is exactly the same. If you can solve the cases - you'll be good no matter who leads the case.