I came across some videos on youtube where women bathe a new born by laying it face down between their legs. Like this and this. In case the video is unavailable, these are my main concerns: There isn't any interaction between the adult and the baby, no attempt is made to comfort the crying baby, the baby is exposed to the water pretty abruptly (even if it's at a comfortable temperature), there's too much rubbing going on - especially the face and head, they flip the baby over by one arm.
One argument I've heard used repeatedly is that people have been doing this for 1000s of years, and they've survived. But I found no literature or scientific evidence for or against this method. This is what I'm looking for.
My question is: is there any evidence or statistics about this method of bathing newborns being safe, or unsafe. Or being a cause for the baby to associate bath time with discomfort. (If there's any discomfort at all)