ichris,
You republished, "Since the hydraulic output (pressure) is essentially constant, the maximum force the actuators can isolate from the pilot remains constant, and under certain circumstances may be exceeded."
That circular logic is simply amazing. Let me restate it:
"Since the servos are too small to take maximum blade forces, there are circumstances where the controls stop being controls, and the pilot might die if he maneuvers too much. By the way, we provide no way to know that maximum, so hold on tight if you blunder across the boundary."
It is a fact that the maximum blade forces during stall are measurable and part of the designer's lexicon - in other words, you don't get more and more force from the blade as you maneuver, because there is a maximum moment the blade can produce, just as there is a maximum lift. The plain facts are that some helicopter designers simply don't bother to build the servos large enough to withstand this maximum force, in fact, they fall so short of the maximum that the controls lock up during relatively gentle maneuvers (at high altitude and at high weight).
Like LTE, where a tail rotor that is too small is allowed, and instead the manufacturer starts to blame the pilot, Jack stall is not a sign of pilot error in all cases, it is a sign of a poorly designed helo that does not have the basic control capability to protect its occupants.
I firmly believe these jack stall designs would never be certified in the US or CAA, they are only allowed because of the bilateral agreements. Bell, Boeing, Sikorsky, Westland and Agusta all have design rules that do not permit jack stall, because they all design the servos to be large enough to withstand the rotor forces, and protect the occupants.