If I am on the Clinch. I will fish BHPT's and midges, both #18 or #20. I have found two flies that honestly kill on certain parts of the river. One fly in particular is so simple that it really is silly. First is my "Church Fly". On any given day in the spring I will go through 4 or 5 of them because they get so torn up by the fish. The other is called a redrum and as Waterborn will attest...it produces in great numbers.
In the end. Does it really matter what you use as long as you have fun?