Sometimes a tree or very large shrub has gotten away from us, and there are inconsistencies in the structure of the tree. Then someone says, HEY! I can see daylight through that fork! Well, sometimes, whether before, or even after, you can add mechanical advantage to keep things together. Simply put, bolts and cables, with a degree of science, support the logic. If you love that tree or shrub, this is sometimes a viable option before removal.