If you're feeding F/T, there's absolutely no point in feeding in a separate container.
With that said, I feed live and ONLY feed in a separate container. I will never feed inside their terrarium. Not only is it dangerous if the snake doesn't kill the prey right away, it's very unsanitary because rats and mice pee and defecate on everything.
I feed 5 snakes weekly and don't have a problem with "stress" or them ever biting me (or even trying for that matter). They are actually conditioned to "know" that once they're in a separate container they will be fed.
People make feeding in separate containers sounds like bad practice but it's really not. Everyone has their way of doing thing. Just have to figure out what works for you.
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