I've flown the plane several times with 30% expo (Spektrum, so positive) on the ailerons now. It has been a great help, as expected. Already, I've increased throws via dual rate and see that a lot of my trouble is pilot trouble. Actually, looking back at my flight log comments on my first Smoothie, I see that I experienced the same thing with that airplane, too. Did not have exponential possibilities on the two radios I used in that airplane in 1980-1984 but just got used to things as they were.
It is still an interesting possible cause of the sensitivity around neutral...........strip ailerons.