It's so simple it's counter intuitive.
You go up to the crane's maximum comfortable reach, and butt tie the tree to itself with nylon slings n shackles, while you're tied to the crane. When you make the release cut, the CO must boom yu up n outta dynamic thrashing range till things cool down enough to retie into the tree, and start pickin n grinnin in earnest.
Done it hundreds of times, with an experienced CO, but never with a rookie CO.
Jomo