Very clever Reg. Necessity is the mother of invention.
In the past life as a production climber i tried a couple techniques as well.
1. Ring & ring Friction Saver; friction saver dedicated for rigging afixed to target limb (suitable union req'd). Set up like a double-whip-tackle system to my cutting postition with a porty for lowering. Once the target limb was on the ground, the friction saver was removed from the limb as you would from aloft, brought back to the canopy and reused.
2. Gri-gri; (exceptionally handy on understaffed jobs, req's groundy)Working end of line attached to target limb, ascends to suitable natural/block rigging point, fall of the line to gri-gri adjacent to work position. Limb is severed, and climber lowers to groundy. Did some fairly large projects with 2 man crew. Pieces were cut so groundy simply untied and humped out of yard (i.e. processed aloft). Climber kept busy, groundy kept busy (i.e. single groundy wasnt buried with a large rig they had to process, leaving the climber to wait) Had a rigging dedicated gri-gri for quit a while for this.