Does This Debunk the "Coolant Can Flow Through the Radiator Too Fast" Idea???

It's impossible for water to flow through a radiator and not shed heat. It cannot happen because of the radiator's design. It's designed to slow water flow just enough to shed the right amount of heat. As long as the radiator is large enough, it'll do the job.
And what is the major function of a T stat but to regulate the flow through the engine.