Waspy said, "A force acts when on one side of the machine, greater in magnitude than it does when on the other side of the machine. This is a fact."
Yes, purely from a peak magnitude, it is a fact. While the peak magnitude of the force on one side is perhaps greater, the curve shape is sharper, and the AVERAGE force is exactly the same. The somewhat lesser peak force peak on the other side has a longer duration (a softer peak) so that the average force on both sides is exactly the same. The net momentum affect (force times time) is precisely the same.
Both you and Jiff are fooled by some idea that the mass can be accelerated on one side differently than the other, all while the mass is physically tied in position. Your inability to picture this trapped mass as chained to an equality of acceleration is what has prolonged this thread. Do you think that this perpetual motion trash has never been thought of?