Twine is fine, every plant responds a little differently and sometimes you just have to feel this out. Even if you were to break or fold your stem in the process of LST, most times the plants recover and continue about their business. I have used everything from twine, hemp, phone cable, twist tie, etc etc.. Here is a pic of lst where the stalk actually folded because of the rapid growth and relative weakness of the stalk, and was using a very sturdy tie with no give. This plant could not care less about that, happily growing as we speak. I like to tie the plant down to itself instead of the container whenever possible.
Your LST is looking good, keep practicing and realize that along the way some lessons you may have to learn the hard way
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