Another variation of this I have done is where you need a rig point that is away from the tree you are working, but the adjacent trees are much much shorter than the tree you are working. I would set it up much like a speed/drift line but because space is limited preventing a full size drift line, I routed the the rigging line through a block on the shorter adjacent tree, and tied it off to the stem I was working at a high point much like a speed line. I then use a sling and omni block on the rigging line to remove tree parts. They slid down the rigging line while the groundmen fed out slack resulting in a basket effect like the double whip tackle. I had a 250' 1/2" stable braid or else this would not have worked for this particular tree. Just thought I'd share that.
