I don't like the way he did that....maybe *that* heat pad won't get too hot without something to regulate it, but the majority of them do. He could have at least found a cheap rheostat to send home with the kid...
He's so lax about it, which is fine b/c he knows what he is doing, but if he's going to make a video and post it, he should at least put in some safety measures (rheostat, thermometer, etc.) so the people watching don't just go buy a little heat pad and plug the thing in.