Tightening rope tensions with a trucker's hitch

I’ve found the trucker’s hitch useful for tightening ropes under higher tensions. Image The upper rope attaches to a fixed point. The carabiner should connect to the spot that will bear the tension we want to tighten. Now, if you replace the loop with a ring device, pulling the free end of the rope makes the part under tension experience twice as much force as your pull. The next image shows this more clearly: Image More complex arrangements are also possible, so theoretically, lifting one’s own weight with just one hand could be feasible. Image