What is the youngest you'd breed a female ball?

[euphuistical]

Power-feeding refers to introducing more food to a snake that is swallowing a meal, to trick it into taking more food than it intended to. Power-feeding can cause 'pin-head syndrome', where the snake's body is disproportionally huge, and its head is too small for it. Feeding on a 5 day schedule, particularly for the first year, doesn't cause any abnormal growth. The snakes develop proportionally and thrive. Ball pythons are very good at refusing food if they've had too much, lol.

I concur, "power feeding" when referring to stuffing more food down a snakes mouth just to add extra weight seems wrong and bad for the snake. But with my snakes I offer food every 3 days or so (I usually feed ASFs, so some of my bigger girls eat a lot of them) and sometimes multiple items and if they eat it great, if they don't I just wait a few days to a week then try again.

To be blunt these are wild animals, and they aren't very smart (but at least smarter than gold fish who will eat too much and cause their stomach to burst heh). If they are hungry they are going to eat, if not they aren't going to (or something in their environment is causing stress, but I think I made myself clear). As long as everything seems ok with them continue with how you want to feed them. I don't really think theres been any rigorous scientific studies done on how often to feed ball pythons at different ages / weights.