Some of this is very individual, some is modality dependent. In my case it's been helpful to talk about my feelings about my therapist and our relationship because a) it helps my therapist make sense of my reactions to the things he says, and b) the way I relate and react to my therapist gives useful insight into some patterns in how I relate to people in the rest of my life. But that's also a big part of how my therapist works, and he's encouraged me to talk about how I feel about therapy and about him. I don't know how it would or wouldn't be helpful with a therapist who works differently.