Thanks for the attempts. Further thoughts lead me to believe it's not the steady-state lift generated according to the lift equation, but how quickly that lift develops when the configuration is changed by the controller. It is obviously not instantaneous, but possibly some function of the sonic velocity and possibly also to do with the (true) speed of the air passing over the wing.
I think it's a sonic velocity issue, from gut feel, as the pressure field around the wing can only change at the speed of sound
More research needed, I think