Interesting tool that bar. I do something similar using a power puller and a hefty length of chain. Cinch the chain about 10' up the tree. lead to another tree down range and attach tackle to it. Pay out the cable thru the block and to the chain. Other end cinched to base of tree. 6-7 pulls once taught can really put some pull on the tree. Then I proceed with the back cut.
Kudos for doing it by hand. The badge is well deserved cuz its a lot of work.
I suggest huckleberry pie. But the only thing on the gluten free menu is this tiny ad:
permaculture bootcamp - learn permaculture through a little hard work