About a year ago, someone shared an article (I don't think it was on mothering) that highlighted the differences in the way that bottle-feeding parents and breast-feeding parents co-slept.
Some points mentionned were that bottle-feeding parents tended to rest baby at head-height, sometimes on a pillow, whereas breast-feeding parents set babe at boob-height, with a protective arm above their head and typcially slept facing their child with their knees up and arm along the top.
There was waking frequency I believe, but it really spoke to the physical differences in how the two types of parents coslept and the protective factors that breastfeeding moms did naturally.
Does this ring any bells for anyone? I've been looking for this article for MONTHS. It actually had pictures too which showed the difference in positioning.