Thanks to all who responded to my lazy S-Tec questions. Though we haven't
yet had a chance to flight test the key suggestions, it appears that a
solution lies somewhere in combining different resistor values in the
computer (going from 18K to 12K) and increasing servo clutch settings.
Though many wrote that they have also experienced increased control
pressures with altitude, the question remains as to what generates this
increased control heaviness -- which is particularly evident in roll.  Some
pilots thought it was involved with pressurization and the changed shape of
the pressure vessel or the counterbalancing forces exerted by boots on the
control rods.  But the Mooney I used to fly exhibited the same extreme
stiffness in the Flight Levels.  That leads me to think that this control
"stiffness" is brought on by aerodynamic forces, thin air, or some other
combination of aeronautical events that are waaaay beyond my knowledge base.
I am very interested in hearing anyone's thoughts on this.  Many thanks
again for all the thoughtful postings.  Jack Cowell