I believe the LS-6 does it that way (flaps and ailerons all even in full
negative flap position) my recollection of the 20 is that everything is even at
zero flap and zero stick. One can set it up as one wishes, but one may be
dialing in undesired consequences.
I remember the Boeing engineer who told me, "Aircraft are designed by geniuses
to be operated by idiots".
JJ Sinclair