I went down to the upscale marine/racing dinghy store and told the fellow what I wanted to do and he said "Check this out...". It's a regular eye splice that you'd do for any braided line but the vectran is so ,,odd? slippery/stiff that when you compress the hollow braid (no core) it balloons out like a chinese finger toy. So using a fid (I think that's what it is) which is like a fat aluminum needle with a hollow end you compress the line, slide the fid in with the end of the line in the hollow end, push it through with a ,,,,pusher(?) and out a couple inches down. If you compress the line at the splice you can pull the loose end and make the loop smaller, pull the loop and anchored end and the line clamps on itself. To release it to make the loop bigger you compress the line on the spliced part and pull the loose end back, the moment you go back to pulling the loop and anchor end it compresses and locks. I've had the setup in a boat for over a year now and it still works.
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