Firm Feel, Hotchkiss, PST and all the others offer bigger sway bars. They increase the cornering spring rate without affecting the straight line rate. That helps keep the car streetable.
Hookes law disagrees with you. F=KX
The spring constant is just that. A constant. That’s one advantage that a coil spring has over T bars. An asymmetrical spring can coil bind at a certain height and the constant for that height change.
