Is it possible to overfeed a hatchling?
It is possible to overfeed any snake. Most people keep their snakes on a diet of one mouse per week. Some do this to keep costs down, especially if they have more than one snake. I also like to think that its more natural since corns (or any snake) in the wild probably do not have access to food/prey as frequently & if they do, they may have to work harder for it. Younger snakes can be feed more frequently without any harm to themselves (3-5 days) but I would suggest only 1 meal per feeding, otherwise they could regurgitate. I think with increasing feeding freq. they just grow faster, but not necessarily bigger. A corns max size is most likely genetics, not meal frequency.
Will they stop when they've had their fill? Probably not, its just instinct...they'll probably just eat & eat & eat.. LOL They are very opportunistic.
I was told by a reliable source that it is safe to feed every 3 days, but if I do this should I cut down on meal size? Some think regular meal size can help corns develop normally i.e. reduce the chance of pinhead (where the corns head is disprop. to their body's size). It is argued that larger food/prey items help with muscle/bone growth. BUT food too large can also lead to regurgitation. I always stick to 1 1/2 X's the girth of the snakes body. PLUS, If you are using pinkies still than you can't really cut down on meal size much further.
Hope I helped ya out a little! Others may disagree since most of what I posted here is just my opinion but oh well!
-Jason