I must be not understanding, you don't mean check on the every 2-5 minutes all through the night right??
And also - re leaving baby unattended. Yeah, you can do that when you only have one. However - once you have more than one baby, sometimes you have to leave one alone for a little while, whilst you are attending to another.
I know someone will get on and tell me their friends with quads or whatever didn't ever leave their babies ever, but that is what I found. I had to separate my twins into different rooms as one could sleep on his own and the other cried 24 hours a day 7 days a week, so yeah, sometimes they are were left to their own devices.