Recently I went on vacation, and it was just easier to put the boys in bed with us (they usually sleep in their cribs). Laying there got me thinking. I have no real fear of rolling over on them, because if I roll over at all it's in the same place, and I consciously roll over, I remember doing it. I'm not one to flop around and move all over.
This is because, when I was a child all the way up through college, I've always slept in a single, or twin sized bed. In college the bed was quite high off the ground. If I rolled over, I fell off the bed. It was as simple as that. I grew up being conditioned to not move around much at night, unless it was in the very same spot.
I'm out of college now, however I took psychology and loved the research end of it. If I ever had to do it again, I think this would be an awesome thing to study: In the case of infant death related to co-sleeping, is the size bed the parent slept in during childhood related to how dangerous co-sleeping is for them? My hypothesis, before doing any research, would be that in many or most of those cases the parent grew up sleeping in at least a full sized bed.
*EDIT* Ok, so through posts it's been made very clear that most likely, my guess is very wrong, lol. Deaths related to co-sleeping are mostly related to the parent being under the influence of a drug or alcohol or medicine that makes them sleep harder, or by not doing co-sleeping correctly (see the guidelines on I think page 5 or 6?). The general idea is that no matter what bed we sleep in, once we are mothers co-sleeping, we don't sleep as deeply, and just like we subconsciously know where the edge of the bed is, we know where the baby is.
Also, you might want to know that this post has somehow devolved into an argument about CIO.