Personally...I would advise against feeding a giant snake outside of its enclosure. When they're small, it seems like a good idea, but when they grow too big, it can become a very dangerous task on two different levels.

First, and most obvious, is the danger of a feeding response. If the snake is not finished with its meal, as Snakemann mentioned in his post...or even if its finished, but still in "hunt" mode, you could be hit with one of their infamous feeding responses. And while a defensive bite might be scary enough...a feeding bite from a giant snake could be deadly. This is a risk you would take each and every time you had to move the snake back and forth from its enclosure to its feeding box.

Second...it can be dangerous for a snake. We all know what too much handling can do to a snake that has just eaten. What happens when you have to wrestle a snake that weighs more than you do, out of a big box and back into its home? They can't be gently scooped up in the palm of your hand, like you did when they were babies. If not done right, this procedure can cause them to regurge.

The argument that if you feed inside the enclosure, you risk a feeding response even when no food is involved, is something that can be easily overcome by consistent and carefully conscientious care. For instance, have two different doors in the enclosure...one always used for feeding and one always used for your own access to the enclosure for every other purpose. And/or, always use a hook to remove the snake from its enclosure...when it sees/feels the hook, it won't associate it with food. And of course, the obvious answer of making sure you NEVER smell like food around the enclosure.