Dick,
Not so sure about you last post – re a power assisted system.
Building my technical argument starting from a fully powered all-flying slab tail (Lightning) and working back. The powered tail surface was positioned to achieve aerodynamic trim whilst stick force was reduced independently via a ‘spring feel’ system.
Splitting such a conceptual system into a trimming tail with a power assisted elevator (Hunter); the tail had to be irreversible thus no force feedback to the pilot, but the pilot probably had some elevator load fed back, thus a need to trim. The elevator maneuvered the aircraft and was positioned to achieve aerodynamic trim (balance); the power assister / pilot holding some residual load. Zero stick force was achieved by a combination of pilot ‘spring feel’ trim and flying tail adjustment. As the load held by the assister / pilot reduces the elevator moves, but there is a corresponding proportional (and opposite) movement of the tail, maintaining the aircraft in aerodynamic trim. A null position is achieved when the elevator and power assisted tail are in line, similar to an all flying tail.
Furthermore, in the Hunter with auto ‘tail follow up’ engaged, this enabled the tail to move automatically to reduce the feel forces; thus during combat the crew did not have to trim with maneuver or speed change. Aahh Hawker, clever people; a bit like an A320 FBW???
Now with flaps down, it all depends on the authority (range of movement) of the tail; I suspect that even in a civil airliner a zero elevator (or optimum design position) can always be achieved.
Sorry for the old aircraft examples, dates me a bit; but there again there were some good old ones.