Ilan, The question is what are you trying to accomplish. Then decide on the best tool to resolve the issue.
For me, I want to get best service out of my lines. I want to be safe on the bow in a blow and not get knocked out by flying metal. I want to have the lines move smoothly across the boat when I tack or gibe.
- Service time. I by a length of line to run up the starboard side, attach to the Jib or Genoa and down the port side. One continuous length.
- I go with the simple idea first. So I use the "Lark Head". Find the middle point of the sheet and run the ends through the loop and down the sides of the boat. Go sailing. It is simple, and safe.
- No metal shackles, no bulky knots, easy to remove the sheets from the sail when storing for the winter. If abused (leaving the lines not freshwater rinsed during the season) then I can use my marlin spike to loosen the knot and inspect/store the sheets.
- If wear appears on the knot after several seasons and the lines are still serviceable, I can cut the line into two pieces.
When two separate sheets are used then I choose the soft shackle method. I prefer to have a stopper knot on the lien the is slid through the loop. It is a bit more bulky but still reduces the opportunity for head damage from a flaying metal shackle.