Only time I've gotten a food related bite was when I was being stupid and handled rats and then tried to reach into my sunglows cage to move her hide she was partially on to make room to feed her. Long story short, snakes can spin around 180 degrees with their neck faster than a human can move their hand out of the way lol. She let go though pretty quick when it didn't taste like a rat. Otherwise if my snakes don't smell food, I can open the doors and reach straight in and grab them. They perk up when the door is opened and start looking around but I'm not sure that is hunger response or just the response to see whats going on.
Me personally I never used hooks. Even my holy terror jungle carpet who struck at anything when I got her, after 3 or 4 bites I got her now to where when she is in doubt, I just put my hand by her face and she sniffs it, knows its me and then just more or less becomes a spazz instead of biting. Now I'm working on unspazzing her which she has good days and bad days. So much feisty and personality in her lol. Most boas are pretty mellow or at least the ones I've seen are. Dumerils are even more so. My little 2 month old dumerils curled up and fell asleep on my hand for about 1.5 hours while I laid in bed watching tv. And this only after 2 weeks of having her lol.
The only snakes I've really heard of being careful around for extra strong feeding responses are retics and burm but then again those snakes get big and I really wouldn't want to get tagged by one of them. I would seriously consider a hook for those guys lol.
Out of the cages, I've never had any of my snakes strike except my carpet who has tried to bite the tv before. She is a bit high strung atm though as I'm still working with her. Everyone else just wants to explore when they come out.