Freewriting Prompts?

Because Wilson Nelson seems to champion the idea of freewriting, I was curious that she didn't specify the kinds of prompts used except in a general sense. I think prompts can inhibit students from writing if they aren't specific enough to generate an idea, so it would have been nice to see some of the specific prompts tutors used. Or did I miss something? Also, I wasn't exactly sure how the freewriting was used: How many opportunities for freewriting were there prior to selecting a topic for a particular assignment? Was freewriting sometimes used as a "warm-up" or as a way to generate discussion and create goodwill among group members?