Just because someones husbandry is different from yours doesn't necessarily mean their animals are sick. Can a female breed at 1000 g,.. yes but it's usually not recommended. Depending on the situation that person may chose age over size even then a young female at that size can still breed. Just like us they all mature at different rates most people just chose to wait until their snakes are larger and weigh more for different reasons. The same goes for feeding, babies or adult not everyone has theirs on the same schedule. No matter what age a healthy snake doesn't have to or even need to eat every week.
More often than not when ever people are involved with something they chose to do what they want, instead of what's best for the animal. Even that (what's best) varies from one to the next.