Heh, I've been bit twice by a couple of my adults, usually during feeding. When I drop the mouse into their feeding bin, they see my hand before they see the dropping mouse and wham!
Most of the bites I experience are by younger snakes. I think most of us out there have a snake named Fiesty for a reason. I've got one 2003 normal het lava that I think has the taste for human blood on her menu. She bites each and every time, doesn't matter the occasion. Of course since she's still a small thing, all I can do is giggle. =P
Tongs are recommended for feeding purposes. It's so they don't associate the sight of your hand with food and consequently bite the hand that feeds them. But for general handling and picking up, I just make sure I don't smell like food and just grab em, show em who's boss of the house.
In all actuality, I find that cat scratches hurt worse than a snake bite. It's the shock of a snake biting that's the clincher, thats what scares people the most. It's that ingrained instinct among humans that snakes can be deadly, and when they bite we revert to "fight or flight" for a split second. My heart rate jumps a few points when I get bit even by the smallest of snakes.
If they do bite, you just have to make sure you don't jerk too much. It can rip their little teeth out and also tends to do more damage to your skin. If you get one that won't let go, go run it's head under running cold water from a faucet, that'll get them to let go humanely and gently.
Just learn what your snake likes or dislikes, learn its habits. It'll learn about you too. I find the more nervous I am handling a particular snake, the more likely I am to be bitten. I think it's like dogs, they sence fear and take advantage of it. So just be assertive, and if they bite just giggle and be patient. =)
Hope that helps.