I handle my bp once a week, usually when I change the substrate on the tub, and only for 15-20 minutes. To my mind, handling is for my own pleasure, not for the snake's, that is why I only take it out as little as possible. Perhaps I am wrong, perhaps they really enjoy being handled and my bp is just dying for me to take it out, but I doubt it. My bp is always very relaxed, only goes out at night and eats like a champ, so I guess he's "happy" this way.
Just my two cents!