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

False. It does no such thing (even tho you found this claim on the internet, and usually they don't let stuff on the internet that's not true).

I tried to avoid the use of the word "vacuum", but I maintain low pressure area created by "centrifugal" force, and the terms "single suction, dual suction pumps" seems to support what I was taught, well before the interweb, lol