I was not referring to the "stick force/g" you referred to.
Then, perhaps, my explanation was inadequate as well, confusing the two considerations .. the concern with static stability is for the pilot to perceive a force tending to return the aircraft to its trim speed condition and is directly related to stick force against speed delta from the trim speed condition. Keep in mind we are talking about stick forces not stick displacement or position. The basic considerations will be the same, whether for a C172 or a B737.
Unfortunately, I have not had the opportunity to fly a variable stability research aircraft so I am unable to provide a detailed "pilot's eye view" of how the experience unfolds.
Perhaps Genghis, or one of the TP fraternity within our group who has done so can offer comment ?
The matter comes down to experimental flying handling qualities assessment, which is a little out of my direct ambit. I did have an incident in my early flying where, due to carelessness on my part, I misloaded an Apache somewhat outside the forward limit. On that occasion, the aircraft was quite flyable but unpleasantly so. The experience, however, caused me to be far more attentive to loading thereafter... certainly, I am only too happy to stay well away from a significant aft CG misloading configuration.
Consider variation from an acceptably stable aircraft, and what that might mean to the pilot's problems, to gain an initial insight into the answer you seek.
We all have a small understanding from our normal flying in that stick force gradient varies within a small range from higher (at forward CG) to lower (at aft CG). This is more so with larger transports having a larger approved CG range and, for these, the effect should be easily observable by the pilot
If the stick force gradient increases signficantly, the aircraft becomes physically tiring and difficult to manoeuvre with an associated concern regarding detail design loads on tail and control run assemblies. A bit like flying a truck, as it were.
If the stick force gradient reduces towards zero, the aircraft becomes progressively more imprecise, tiring, and anxiety producing for the pilot to fly. A bit like trying to ride a big beach ball in a disturbed sea, I should imagine ..
If the stick force reverses (static instability), then the workload to fly is increased dramatically. Recall this means that, from the trim speed condition, a decrease/increase in speed (due to whatever initiator - not necessarily pilot input) then requires a varying push/pull load to maintain below/above trim speed speeds.
Think carefully about that for a moment and the hand-brain stress associated with keeping such an aircraft under control given that all our experience, intuition and exposure is for the reverse loading pattern. Think, also, about the immediate adverse consequences if the pilot gets it wrong .. which is the usual outcome.
I can relate the description given by one TP who was caught in such a predicament during a flight test as a consequence of inadvertent gross misloading for the test point. His observations were that
(a) unless one recognised (immediately) what the problem was .. and the technique needed to control it, the outcome would be quick and inevitable. Certainly, the accident records have many examples of loss of control (with a subsequent hull loss) following significant loading excursions outside the aft CG - a commonplace initiator for an unacceptable static stability condition.
(b) flying technique involved numerous short, sharp control inputs to put the nose where it needed to be (ie stick movement remains normal) and then freezing the control position to avoid the variable loading perceptual problem.
He managed to continue this long enough to drag the aircraft around the circuit and throw it back onto the ground. His commentary suggested that it would not be desirable to have continued for much longer in such a high workload situation. If one notes that this particular TP is a very experienced trainer of TPs .. puts the observation in some sort of perspective, I think ...
Although not specific in his comments .. he made some side references to a (presumably) quite robust technical discussion immediately following with his FTE .. the latter had been responsible for the loading calculation error. One certainly gained the impression that the particular TP was less than happy about the hazard to which the program and crew had been exposed.
Those of us who don't venture outside acceptable handling qualities in our flying are protected by the collective and historical wisdom gained by those who have done so in the past and continue to do so now.