Al,
I could go the route of others and just say you're wrong and scream
misinformation and start another thread, but I prefer to do things differently.
The tree doesn't know what is holding the branch down Al. Snow, it's own weight, a fallen branch, coiled wired, a string with weights or a guy wire. A tree doesn't know and a tree could care less.
The fact of the matter is that after lowering a branch, the tree is out of "balance" (see my other
articles) and the tree will respond by attempting to raise the branch back to it's rightful position. You see after we lower a branch by whatever means the new wood cells change their secondary wall differentiation to produce totally different levels of growth stresses, the upper side of the branch tries to shrink by producing higher tensile stress and the lower side tries to expand by producing wood with lower tensile stress or even with compressive stress. The result being an uneven distribution of growth stress that bend the branch back up toward vertical.
In soft woods like pine the underside of the branch creates compression wood, in Hardwoods like Maples the upper side of the branch develops tension wood. Compression wood pushes and tension wood pulls.
I explained all this so that we could understand that A tree will react the same way, no matter why the branch is being pulled (or pushed) down. This being said, Guy wired have their purpose and a limited one at that. Regular wiring is much more effective only because you can wire in three dimensions instead of the two given with guy wires.
Will Heath