Originally Posted by NautiG
SD, I also tried setting up some jack lines for the first time. The best I could figure out was tying to the mast where the spinnaker pole hooks in about six feet up. This kept my tether from tangling too bad on hand holds etc on the deck, allowed me to clip on in the cockpit, and reach the bow.
I still would be dragged along overboard if I fell near the mast. I'm still not sure of the wisdom of the jacklines. I'm a good swimmer and often wear a wetsuit while single handing. I feel like I'd have a fighting chance if I went over a mile or two from shore.
On the other hand, if I'm clipped in and fall over, I could be dragged for miles and miles. My boat really does sail itself on a reach for hours at a time sometimes.
Gemini Catamaran Split Decision
The jacklines should not run all the way aft. They should stop at a distance forward of the stern that is no less than the length of your tether.
Also, it's best to have a quick release on the tether where it attaches to the harness. That way you can "let go" if circumstances demand it (for instance, if you're being drowned). The quick release needs to be a "high load" version, i.e. one that can still be released while under tremendous pressure/load.