Conventional Pitch Response and Fs/g
Microburst2002 - The section you have quoted points to the notion that at low speeds a commercial transport pilot tends to regulate the magnitude of the pitch response based on the pitch rate achieved. At low speeds considerable pitch rate can be produced with relatively low normal acceleration. For example, pilot training ususally targets a desired pitch rate during takeoff rotation/climbout, go-around, and flare maneuvers. At high speed the cue that the pilot tends to pay most attention to is Nz as the associated pitch rates are very low.
You are spot on with your reference to stick force per g. Fs/g is a handling qualities parameter that is a focus of control law design. The aim is to keep Fs/g fairly constant throughout the flight envelope. For pitch control laws that use controller position as their input (as is the case with the 777), both the controller force/displacement characteristics and the gearing between controller position and C*U command must be considered to determine the resultant Fs/g.
On an airplane that has a direct mechanical cable connection between the pitch controller and the elevator, the force/displacement characteristics (i.e., the stiffness) of the controller are a function of impact pressure as elevator hinge moments go up with increased speed. For the 777 Boeing decided that having the column become stiffer as impact pressure increases is a situational awareness characteristic worth retaining. This is a point of intentional differentiation between Boeing's fbw philosophy and that of Airbus. The 777 stick force per degree of column travel increases by a factor of about 3 from low speed to high speed. Having the abililty within the C*U control law to vary column stiffness also allows using that same feature to provide additional pilot awareness as part of the 777 envelope protection functionality.