Great question — answering as the UphillTech team:
I haven't found anything on this looking around, so I'll approach it from a different perspective - why not slide a small piece of thicker material round the thin guyline as a sleeve? You could then keep this sleeve on each guyline, and go as thin as you want to without worrying about it cutting through the attaching point. I would imagine that the tension on the guy line would hold it in place well if it was a snug enough fit.
Full answer by berry120: https://outdoors.stackexchange.com/a/3886 (CC BY-SA 4.0).
Need it done for your business? UphillTech.
