I feed in a separate enclosure, a large size bankers box that absolutely reeks of rodent death by now, lol. My bp goes into food mode as soon as I place her inside. I definitely think that conditioning has a lot to do with it. I've tried to feed her thawed rodents inside her enclosure and she wanted nothing to do with them in there, but then I took her out and put her in the box and she nailed it.

Its not necessarily stressful on the snake to be removed from the food box and back to their normal enclosure when they are done. My bp has never been aggressive towards me after a meal, and although she's clearly in food mode, she quickly goes into hide and digest mode immediately after I place her back in her enclosure.