The new fly fisher, don't be moving your rod left and right as much. I know your trying to apply pressure against the direction of the fish. Your only going to work your hook loose from the jaw creating a hole. Eventually the fish the hook will loose its effectiveness and only be holding on by the edge of the hole you've created. This allows the fish to shake the hook more easily. This is especially true with species with hard mouths like salmon and trout. This factor comes more into play with barbless hooks. Cheers.
