Some here have stated that the T-stat is constantly opening and closing as you drive. That is how your house HVAC works (on-off control), but would surprise me if true for the engine coolant control
My reference to "modulation/oscillation" is in the context of a gas pedal maintaining a constant speed by slightly adjusting the opening and closing of the throttle on a hilly road - not slamming totally open/close as a HVAC being turned on or off. Hence the vid.
Thnx Bill