LOL at one point, when I offer food to one of my BP's, he just goes towards it... slowly opens his mouth... and starts swallowing. No constricting or anything. He's only done this twice though. Any other times, he's struck hard and fast.

Often they'll strike and constrict, let go and start sniffing it, and then give up if they don't find the head within a couple minutes. That's the most frustrating. Then I have to re-heat and offer again, and they'll strike and constrict again, as if nothing happened.