Also...I know this might sound like I am having a pop at those of us who have to use daycare.
BUT I have noticed a kind of inverse parallel thing (not sure what you call it) where the more you delegate, or share, the childcare responsibility, the more likely you are to be able to switch off the part of your brain that says 'you have a baby'.
So for example when I was younger and had ds1, my mother lived round the corner and she came over to help, a LOT. My mind was not fully geared up to take responsibility - so I would sometimes feel annoyed if she Couldn't come over, for some reason. Mostly I was with ds, but when I wasn't, I had to switch off the brain messages, the instincts, as in those moments, I was nOT holding a baby, someone else was in charge of him.
I'm not saying no one should have any help. But I know people who share parenting with a partner they no longer live with, and they are always behaving like they almost FEEL it's not their responsibility, because, you know, the boundaries aren't very clear and it could just as easily be the other parent's job.
But more simply, when your baby is at a nursery you aren't using the instincts that say 'you have a baby', that might be a good kind of buffer to stop this sort of thing happening, SO, it might follow that it is easier for people to forget their child is with them if they are USED to switching off the triggers, the alarm system in their heads, for extended periods every day.
I think a lot of people don't even want to send their child to nursery and go to work, especially when the baby is very little. Circumstances and our society make it very hard to resist the push to go to work though.
I am not sure what I am trying to say here, probably that we have got very good instincts and that we should make the most of them.