I've been in on a couple of the interview sessions they do for YPA articles... an elder took all the teens and 20-somethings in the hall into the library, started a tape recorder, and then asked questions and anyone in the group who wanted to speak volunteered the answers.
I guess that if he thought that any of the answers were "good", he would get together with the kid and they would hammer it out into the sort of polished, WT-acceptable quote that you see in the articles.