I absolutely love knowing things about my T (I finally just broke and asked her if she liked coffee, lol) but I think I prefer that all the knowledge i'm given about her comes directly from her mouth and is meant for me to know. That way I don't feel like i'm imposing on her personal life and yet we can still develop a somewhat close relationship. It probably helps that T does quite a bit of self disclosure, so I don't feel the need to have a power struggle with her about the little things. I do think that it completely doesn't matter or can completely enhance the client/T relationship to know personal information about T, without much room in the middle.