[petermat]

Jack,
Thanks for the info - the video in particular answered all my queries on how it works.

I can see uses, but in my current state of slowly decreasing ignorance, I seem to see one significant limitation. With a spinnaker type snap shackle, or a regular shackle with a bar, you can attach a line to the shackle by knot, whip or splice, and be confident that the shackle and line will stay together. I mean particularly while not in use. This does not seem possible with the soft shackle as shown. If one simply put an eye splice in the end of the sheet / halyard ... then the eye end of the shackle is likely to easily slip through the eye splice. One cannot seize or sew anything to the soft shackle as portraid, since the cover of the soft shackle line must be able to move over its core. The only way I can see of meeting this requirement would be to make the soft shackle with a very much longer loop, seized in the middle making a figure 8 with one loop the disconectable part. This disconectable part would have to be long enough that the cover could be pulled back enough despite the seizing.

Or am I still missing something?

Peter