I also feed my snakes twice a week. if you continue to feed like this past the 500 gram mark, many females will hit a weight around 800 grams and go off feed. you will get some females that will continue to feed twice a week past the 800 gram mark. all the females that I got up to size like this. only one that I had to slow her feeding down being that she was getting too big for her length. she was a spider. I feel that you should feed your snakes well, most will know that they had enough to eat before you do. (going off feed) the ones that don't, you have the option of slowing their feeding down if you feel it's needed.

power feeding, this is just my opinion, is when your snake eats and you know it's most likely done feeding. and you feed it more. by sticking another rodent in the mouth right behind the one it just ate or by force feeding again and again over time.

a snake thats eat on it's own, how can you consider that power feeding?

if you feed your snake every 7 days or whatever. if the snake has a good look (weight to length) I don't see anything wrong with that. if you're going to breed that female, I hope she has the added weight to help support a healthy clutch of eggs and maintain her health.