Well, last night while practicing, I thought hmmm, let's check this swivel thing out and see if it does anything differently. The answer I found is that yes it does change things. . . for the worse. I took the whip, threw it fairly hard, and then quickly lost control with the stout leather flailing out of control. It came back, popped my square on top of my head, and sat me on my butt with a throbbing headache and a few spots of blood. For some reason, I wasn't wearing my Camptown fed which probably would have protected me at least a little. It definately would have deepened the center dent for sure.
The reason I am telling you guys this horribly embarrassing story is that it's always good to hear of someone else being incredibly stupid and unsafe so you don't have to do it yourself.
Just a reminder: BE CAREFUL. These devices can really hurt. And you feel like an idiot sitting there in the grass bleeding and holding the source of your pain, a lengthy piece of leather, in your own hand.
Regardless, don't follow my example.
Cheers,
Chaos