Anything tied to a branch or trunk will leave a mark where it pushes hard against the bark. The tighter you tie the deeper the mark will be. The thinner the line/wire/twine/etc is the deeper the mark tends to be.
Thread the line through plastic tube or cushion with rubber will help spread the load and reduce marks. Definitely never tie anything tight right round a branch. If it is left long enough that will cut off circulation and therefore kill the part past the tie.
Guy lines of any sort are useful to move parts of a tree but are limited to movement on a single direction - straight toward the pull point. Conventional spiral wiring has the distinct advantage of moving in a direction where there is no pull point or in several different directions - curls, s bend, etc
I guess if you are a fisher you know how to tie mono knots but many will have trouble getting the knots to say tight.
As always, use what you have on hand that works for the purpose and is convenient to use.
As always remove any ties or wires as soon as they start to mark bark. Bends are usually set in weeks or months. There's rarely need to have wires on for years.