Therrin,
Thanks for the PM on this.
It's quite scary how the 'biner opened in your experiment. I have had issues with "self lockers" not closing due to sap or bark caught in the mechanism.
As with all snaps amd connecting hardware, I believe you should always LOOK when connecting, not rely soley on feel or sound. I'll have a bit of a play tomorrow and see if I can replicate your experiment with my gear.
Cheers,
Steve
