The problem is that they did both, and then in their analysis of the results they do not distinguish between the results from a shared chat context, vs the resu

The problem is that they did both, and then in their analysis of the results they do not distinguish between the results from a shared chat context, vs the results from isolated, independent chat sessions. This allows them to cherry pick the best or worst results from either testing technique, depending on which they think is more or less of a "hallucination". The process is flawed, therefore the results are flawed.