If I were a therapist I would much rather my client talked to me. Writing is okay once in a while or for notes to yourself to make sure you cover everything you want to. But actual talking communicates in a way that writing just can't. Intonation, emphasis, posture, body movements including frowning, smiling, wincing, looking down at the floor... Maybe it's better than nothing, but I don't think you're getting full value from your sessions that way.