I truly believe that how many weeks/months/years it takes for a baby to start sleeping through the night is out of the parents' control, every baby is different and they will sleep through in their own time. Night wakings can't be controlled, aside from making sure baby has enough milk/stimulation in the day and hoping for the best it's basically the luck of the draw!
DH however thinks that, medical reasons aside, almost all babies are able to sleep though the night after the newborn stage, and they if they don't, it's because of something the parents are doing/not doing (though of course he is unable to pinpoint these magic actions/inactions).
Who do you think is BU?