Jerry, you should put out a book on "myths, legends, and un-truths in the old car hobby"
I called them "Old mechanics' tales" back when I was teaching- - - -sort of like "Old wives' tales"! What might have been good advice 75 years ago is totally wrong now, in a lot of situations. "Keep a hot engine running when you pour water into the radiator!"- - - -good advice if you're filling a Model T with no water pump, but that advice went out of date in 1928 when they put a pump on the Model A! The only way to add water to an overheated engine these days is to wait until it's a cold engine! Plenty of similar situations out there!
It was not uncommon to get a kid in my class with a father, grandfather, uncle, or cousin in the auto repair business who had all the answers, no matter what the question might be, and quite often the advice they were giving was so far off the wall it was laughable. Of course, as soon as I tried to correct the misinformation the kid had been fed, the oldtimer got his feathers ruffled and called me all sorts of nasty names! Now the kid is in the middle- - - -I expect him to do it my way, and someone he loves and respects has a different opinion! Teaching is fun!
Jerry