Maybe I posed the question the wrong way. Assuming the pivot point is on the scale 20% MAC, would-or should- the stab be 'balanced' at that point with no linkage connected. That is, would it 'sit' level. Indeed, I recall most jet stabs hang tail heavy. I assume full size, and models too, are attempting to put the least strain on the actuator, or servo. Maybe there are other reasons aerodynamically for their design and balance-or being purposely weighted to hang aft.