> linked most highly to success in therapy is the strength of the relationship between therapist and client

Have there been many studies looking at how the client-therapist relationship itself effects the client? Wouldn't having a non-judgmental person with whom you can comfortably confide it, whom you know is making a concerted effort to help you improve your well being, have some noticeable improvement on your condition, regardless of whether they were a trained professional?

Or put another way, is there anyone who finds themselves in therapy largely because they have no close friends?