When I had Matt, it was his first time being a TA in a course, so there were times he stumbled. There were a lot of times during the semester when it felt like he didn't exactly know what was going on in the course and the professor didn't really convey his expectations or plans to him. Either way, I don't think it was really Matt's fault that some of the grading in the course was frustrating. He was always available to talk during office hours and email, and he was happy to answer any questions. Overall, I think Matt was a decent TA in his first semester, but I could definitely see him growing into a great TA with more experience.