I feel like I have to throw away almost all advice they give us about kids these days. These types of things do a lot to undermine the advice of doctors.
The latter by the way led to a dramatic increase in incidents of Sudden Infant Death Syndrome causing us to roll out the "back to sleep" movement.
Many still disapprove of sleeping next to your baby despite it being as safe - safer in some instances - than sleeping in a crib and providing a protective effect against SIDS via the parents breathing/heartbeat as rhythm keeping and carbon dioxide that triggers regular breathing.
You basically have to take all parenting advice (even from a doctor) with a grain of salt and at the end of the day do what you as the child's guardian feel is best, especially because no one style or technique will work for all children.
And I use "feel" explicitly because often on more subtle issues there wont be a clear answer, even from your doctor.