I actually feed in the cage, I used a shoe box but never really liked it. Feeding outside the cage is a good idea. It is more for the keepers safety, doesn't make any difference to the snake. I've never been bitten while going to pick up any of my snakes either. In fact the only time I've ever gotten bitten while feeding was when I was feeding outside the cage. That was my fault tho, and man can they bite.
Feeding outside the cage is great practice for big boid owners. Such as burms, retics, ect. If you have a big boid that can kill you in minutes you'd take any step to prevent that.
It's all the owners opinion. But often picking them up and moving them to a special feeding area can make them not eat. I've had my babies refuse when I've held them right before. So I wait 10 mins and come back.