If a Roman Catholic or Orthodox Church member wants to appeal to this verse to refute Sola Scriptura, then he is shooting himself in the foot because Paul himself says that his writing, which is Scripture, is what the church is to submit to. Furthermore, he is behaving as a Protestant who holds to the doctrine of Sola Scriptura by appealing to the authority of Scripture.
In addition, he is using the authority of Scripture, in a sense, to refute the idea that Scripture has authority over the church. But, we see from Paul's statement in the verse that his letter is there to tell the church how to behave. In other words, the church is to submit to Scripture--not Scripture to the church. It is not the tradition that informs the word of God but the word of God that informs tradition in the church. -slick