How sticky is the back side of the tape, and how strong is it?? This stuff might be a good solution for making sail slugs slide up and down a mast more easily.
I think you could try it and see. The tape is quite substantial but I have no idea how it would stand up to UV. The adhesive seems pretty sticky but I have only used it indoors and a predictable, back and forth, movement between surfaces. It certainly does reduce friction a great deal so if it could stand up to being used like this it would be good. It is not cheap, although you could cut each strip into three to go on the inside of the mast slot.