srm wrote:
The clew is moving the exact same distance whether the blocks are attached directly to the sail or to a pigtail. Therefore, the exact same amount of line must pass through the blocks during a tack, so you are working the same amount of sheet per tack.
All the pigtail does is eliminate a length of "dead" sheet. The reduction in the amount of sheet is equal to two times the length of the pigtail for a 2:1 jib sheet system, but then you have to add in the length of the pigtail, so effectively you have reduced the amount of jib line on the boat by the length of the pigtail.
Exactly. It's still a 2:1 purchase, so you will still need to pull in the same amount of jib sheet. The clew of the jib (or the pulley/sheave on the end of the pigtail) will move exactly half of the distance as the length of sheet that is pulled in, and this is true whether the pulley is fixed directly to the clew or to a pigtail. However, by effectively moving the pulley closer to the jib block, you are eliminating the need for a length of doubled up jibsheet.
The pigtails reduce the overall length of jib sheet needed, and reduces weight on the clew of the jib, which is very helpful downwind and in light air. That is the primary reason to use pigtails. It does not reduce the amount of jib sheet on the trampoline, nor the amount of sheet you need to pull in or let out when tacking.