Ah, yes I only think it would work for leaders. I was skeptical but now I've had many snags and it's at least stronger than my 80lb test. I've been tightening them as much as I can with pliers while wrapping the leader in the other hand (wearing a thick glove) so while they work I feel I have to pull pretty hard, it would be impossible to do without pliers. I haven't tried that one I will have to give it a try. I've been using this one Link Title
Just sharing I'm not claiming the video is true that it's the strongest lol.
I haven't worked with leaders myself, any time I used one it was pre-made with a snap swivel on it. This knot would only work well on leaders, not so much a standard monofilament--my favorite for that is the palomar knot.