Soft Halyard or Line Shackle

[Brion Toss]

Hi,
I used a fairly blunt taper, just cutting a 45 on the ends. That's one of the things I want to change for the next batch. As for the cutting problem, it happened, as I understand it, with a Spectra/Spectra connection, with a shackle of HSR, and a lanyard of the softer SK78. With a Dacron lanyard, it might be a self-solving problem, mostly because the Dacron should be at least 3 times the diameter of the HSR.
Fair leads,
Brion
PS,
You can see a video of a shackle break here:
https://www.facebook.com/brion.toss