I'm not sure what you meant by this is an incorrect understanding. Your understanding of the gas pressurization is the same as mine. But at only 25#, times the area of the piston, you're only adding a very small additional resistance from the gas pressurization. That's why I asked. If the valving is significantly different, then that answers my question.that is an incorrect understanding.
there is approximately a 25# gas charge. this is constantly pushing. as proof, if you remove the shocks and compress them, they will extend on their own. the standard shock, which has no gas, will not. this pressure, and the valving and inherent resulting resistance associated with it, causes every bump to be met with resistance that results in jitteryness.
My question was based on the fact that my car is a hybrid. It is not an M030 car, but a previous owner had the M030 rear shocks/helper springs added. Having autox'd it just a bit, I can say that it still has a lot of push (at least one other very experienced autocrosser who has been in my car also noted how strong the understeer was). I recently purchased the adj. rear M030 bar to see if I can dial down the understeer, so it still is on that side of neutral, but can be coaxed to neutral or even oversteer with the right driver inputs. I'll find out later in March with the first autox of the season.
Additionally, I want a car as has been espoused above that I can enjoy driving. This is a lot more important to me than being competitive on the track. So I'm interested in real knowledge from other weekend racers if anyone knows how a hybrid like mine will act. Maybe I don't understand what jittery is, or how nice a pure non-M030 car rides, as I find my car very driveable on our fun back roads. It never seems harsh to me unless the road is really bad. Otherwise I like the ride, but maybe I don't know how good it can be.