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

Ok I’ll give my real life experience, the engine got so hot it melted the bond between the insulator and metal base of each spark plug (could wiggle them all) causing 2, (iirc) plugs to fall out of the head still with wire attached. I stopped (going down interstate 81) because I heard the popping noise, there was no indication it was overheating (idiot light didn’t work) after cooling on side of road I got the 2 plugs back in the head then drove to a gas station. The attendant was getting off shift and said he would drive over the store to get me 8 plugs. He loaned me the SP wrench to replace, $20 (1968) so after getting to my girlfriends house in Roanoke (with no tools) a neighbor said I ought to check TS, found out it didn’t have one so put one in, also wire was off heat sending unit. On 4 hour drive back it NEVER overheated again (checking every 30-40 miles). I had opened the radiator cap before adding TS and water look like river rapids, after TS and hot it barely moved. Driving around town it might have never been a problem but going up the mountain out of Charlottesville it pushed it past its comfort zone then going 65 down 81 made it worse.