Don't turn the needle in until the engine begins to sag. Just do the pinch test, and continue to lean the needle valve for as long as the engine picks up rpm each time you pinch. When it no longer gains rpm with the quick pinch, back off the needle to the last place it did and fly with that setting.

Fuel is cheap, engines are not. If you normally run them flat out, they lose the piston and liner fit much much faster.