My mother is a ped, I know for a fact that she uses her own experience of parenting as a basis for everything. Even though she was never home
(That's not slam against working moms- I AM one- she chose to spend her free time without her kids around, even on weekends, etc).
Get this- neither my sister or I had any issues with teething, supposedly, and therefore she thinks no babies do. She literally doesn't believe teething upsets or hurts babies ever, at all. She also told me to "start putting DD down more" when she was about 2 months old, suggested CIO, thought pedialyte was more hydrating for a newborn than breastmilk, I could go on forever. Having two parents as MDs has made me naturally rebellious towards them! Actually, my dad is great, he's a general surgeon and if you ask him a question about something that's outside of his particular knowledge base, he's super honest about it. I love doctors who will say "I don't know." Pediatricians don't seem to do that often, though!
/sorry for the tangent!