i have always fed all my snakes in their enclosures. even tho i am relatively new to balls, i have done this with boas, emmies, burms, and GTPs as well. i have not noticed an automatic feeding response whenever i put my hand in and my opinion is that until i start to smell like a feeder item, then i am probably pretty safe. that being said, i also no longer use any wood type stuff for substrate either. not so much an impaction problem but i have had to pull splinters out of angry mouths on more than one occasion and had a red-tail boa get mouthrot due to a piece of bedding lodged in his gum towards the back of his mouth and out of sight. my .02 for what its worth.