[brandall10]

My understanding is it's about attention.

When you give it a specific role it essentially hones in on the relevant part of the training data. Researcher in X field? Papers from that field get priority in formulating responses and the accuracy of token prediction for contextually relevant tasks goes up.

OTOH, if you try to go 'meta' - ie. you give it a scenario where it imagines a group of scholars chatting with each other, then it hones in on situations where there is a dialogue amongst a group (ie. a play/script).