Geoff -- I mean to bring this up in my last post, but see I forgot it.

You say that infant suckling at the breast and sucking on the bottle are the same thing.  I don't believe this true most of the time.  If the bottle nipple were better shaped to compress and suck back into the throat, perhaps yes...
but I see many babies who are sucking the milk out, not compressing it out.
 For one thing, many parents do not get bottles far enough into the babies mouth; do not supply pressure under babies chin to teach the baby to compress.  Furthermore I see many babies gagging when the bottle nipple is placed correctly.  

Finally, I never see breastmilk leaking out of the sides of breastfeeding babies' mouths.  In part because the nipple is pulled so far back, it can only go down.  And in part because mom's nipple becomes perfectly shaped to baby's mouth.  There is no  collection of milk in the front of the mouth when baby is latched properly.

With bottle nipples, even NUK type, the nipples do not shape to the baby, the baby must shape to the bottle, and often doesn't.  With bottles, babies often are found to have full mouths, and almost never don't dribble along side the nipple while eating.

Sincerely,  Chanita