I know that article. I think that it should be additionally noted that the original intent was to find free horsepower in reducing parasitic looses within the pump itself.
The mention of the point at which the pump impeller causes cavitation is significant. The recommendations to me are predominantly for racing purposes.
Considering those for a primarily street driven car should be taken cautiously.
I never tried Gary Halls "Phoenix radiator" but I think it is just a thicker brass radiator and that is where the additional cooling capacity originates from?
There also was some discussion about increasing the diameter of the coolant pipes running under the floor and running 100% coolant without any water.
Also a brass radiator is more efficient then the aluminum ones.
Hall said that in his experience the only advantage to the aluminum radiator was weight reduction for getting the cars weight down for racing.
Increasing the engine cubic inch displacement will also increase the amount of heat generated into the cooling system. A big displacement engine is just going to run hotter.
I know from experience that the Ford FE engines can be a real bummer to restart hot in the summer. It doesn't even need to be a monster. 390's will do that.
I've seen completely stock FE's boil the fuel out of the carb within seconds of shutting them off in the summer.
All of these factors should be considered.