Well, it kept a snake in. We killed one and tossed it in the run for the chickens to eat. I guess it had a bit more life left and it got all tangled up in the netting while trying to get out of the run.
I think the trick to the netting is what you saw in the video. Loosely about, not tight and neat. If it was placed tightly, I imagine a determined snake may very well break it. It's flimsy stuff.
I have it between my hoop coop "walls" and predator apron. Since placing it, I've not had a single snake in it other than the one I mentioned above. I have had to put some of it back in place from time to time because mice will move it to get to the chicken feed. I fixed that, too. Grandpa's Feeders eliminated mice stealing chicken feed.