A permanent guy system was ruled out because there is no adequate anchor opposite the lean.
Props were ruled out because they would require some mix of large props, footers, framework etc.
Through bolting is still a possibility, but bracing an already split shell may not provide a lot of additional support.
The thought now is something between reduction and retrenchment.
To make the tree safe to climb, we removed the one support rope, and installed two separate ropes each of which was set up as runner tackle (so each provided approximately a 2:1 MA), and one set up as a single line tied directly to the tree (1:1 MA). All three support lines were tensioned with a 10:1 pulley system. The binder straps were left as they were.
A plumb line had been discussed over a year ago, but never installed.
The owner, however, did contribute his own clever technique. He placed pieces of duct tape across the crack in several places, then used calipers to measure the size of the crack at each piece of tape. That measurement was then written on the tape so that progress could be measured both during the job and after the work was completed. He also draw a line on each piece of tape directly at each edge of the crack to make sure it was lined up properly if it became loose. Also, when the tape was put on it was taut, so any closing of the crack would be shown by a bit of slack in the tape. Even in the photo each piece of tape shows some slack, indicating that the crack has already started to close.
<font color="purple"> Photo 17 owner's addition (see attachment)</font>
