Comment by barbegal

Only 2 students actually used an LLM in his exam, one well and one poorly so I'm not sure there is much you can draw from this experience.

In my experience LLMs can significantly speed up the process of solving exam questions. They can surface relevant material I don't know about, they can remember how other similar problems are solved a lot better than I can and they can check for any mistakes in my answer. Yes when you get into very niche areas they start to fail (and often in a misleading way) but if you run through practise papers at all you can tell this and either avoid using the LLM or do some fine tuning on past papers.