The problem is you would need to repeat this experiment every day for 8 months - and even then that's not enough data for a new parent to be confident. It only needs to go wrong once remember.

You're playing the odds. Some children die because they get accidentally smothered in their parent's beds. You can either take the (very small) risk that this will happen and sleep with your child in bed, or you can just not play the game at all.

And for most, I think whilst the reward is "good", the failure is just unthinkably horrific.