... why I do so much pull work w heavy line and TirforUsing Dutchman's and tapered hinges (cut-off corners and bore-cuts) to swing trees, with side favor, be the side favor by limb weight or lean, or any combination of both, has never proven to be an exact science, and never will.
The theories supporting the methods may seem intuitive to the layman. Hold a little wood here, and tickle a little there. It's magic! Wow! Oh... no...!!
As I said somewhere, once before, it's fun to play with the theories -- in wide and open lays, but when the chips come down to the money you better back it up!
Rigging, when set right, is proven science.