Phage I didn't take offence to what you said, I could have but decided not too. Each to their own and to what works best for them selves. No harm done.
All I can say is that when the eggs were sitting still in the bator they were growing, when they were placed under the hen they died. Do the math. Myth or not, take it how you want.
The chick was hatched under a hen, when I got the eggs in the mail ALL the air sacks were broke, so I left the eggs sit a few days, then placed them in the bator with the turner turned off for the first week, the 2nd week I had 8 eggs growing, my better half talked me into putting the eggs under...