I talked to a man at the Desert Extrusion booth at GIE-EXPO several years ago. He said that in the manufacturing process there is a percentage of water used in the trimmer line. When the line dries out over time it get more brittle. He recommended soaking the line in water but not more than once.
For years now I have cut line to the lengths that I need and keep it in an ice cream bucket with a little water in the bottom. The fresh line is always more pliable than the last of the line in the trimmer head. One place where I notice a difference in the water soaked line and the dried out line is in a cemetery that I mow. It works for me.
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