Keep in mind too....a dangling, dancing rat can be kinda scary. I think the 2 most important things to focus on when offering a thawed rodent to a bp is temperature and the way it is offered.
Make sure the rodent is warm. Pretty simple to do via heat lamp.
Second, when you are dangling the rodent, do it at a relative distance from the snake to get its attention. I usually dangle the rat in one place and my bp will cautiously move towards it, then eventually strike. I've seen a friend of mine wave a thawed rodent around a snakes face, anctually hit it in the head with it, and the snake would just recoil back and lose any interest in feeding. Key is to make it seem like it is alive, but from the snake's perspective, not aware that there is a snake coming to eat it. Know what I mean?