glimmer - babies sometimes graze, sometimes feed more regularly, sometimes have one breast only ever, sometimes only ever have two, sometimes chop and change....as long as the mother is feeding responsively, and taking the lead from her baby, all these will work. Why? Because we are not all the same and our babies are not all the same and as a partnership (mother and baby) every one is unique...we're not all cut out according to a pattern, or engineered like robots Mothers have different storage capacities in their breasts (nothing to do with size of breasts); babies have different appetites and different rates of growing.
It makes no sense to be guided by a clock or a book on routines or what next door's baby did, or what your best friend did.
'Grazing' is how most of the pre-industrial world breastfed and still breastfeed - baby is attached to mum, and takes the breast with minimal signalling, and mum feeds without much thinking about it, a lot of the time. This usually results in many, many shortish feeds - probably 2 or 3 an hour for a lot of the day and night. These babies thrive. This is not essential to thrive - most babies can feed a lot less than this, and still do fine. But once you start imposing long gaps on a baby, you might run into trouble with supply.
People like Sparkly's dietician think that babies need to stay on the breast a long time, in order to 'reach' the hindmilk. Not true. The grazing baby gets relatively high fat milk, because of short gaps between the feeds, and because the breasts never get really, really full. The fuller the breast, the less fatty the milk; the emptier the breast, the more fatty the milk. Babies feeding like this also get large volumes - all those shortish feeds add up to a lot of milk.
Babies engineer their own intake perfectly well, usually
Hope this helps you understand. The kellymom website has some good explanations, too.