RE: Hitec Optic 6 Ch5 Gear expo
EXPO is only available on channel 1, 2 and 4 with an Optic 6. Or with slaved channels driven from 1, 2 and 4. See page 28 of the Optic manual (bottom left hand corner), it clearly states that the Optic allows EXPO for ailerons, elevator and rudder.
What are you using channel five for that would require EXPO?
EXPO at no time would be notable while spinning a knob on the Futaba to the best of my knowledge (unless you’re holding a stick over or partially deflected). Expo either softens control response or makes it more sensitive around neutral.