Is anyone using the metal shock absorber from the Petzl Zyper [1] as their center cowstail attachment? To do so requires completely destroying the Zyper and re-threading the metal piece with your own dynamic rope. I've been using this rig for a few months and really like it. It is a really dynamic system and allows on-the-fly adjustment of the cowstail lengths. Couple questions:
1. Are there any safety concerns?
2. What size rope is best? I'm using 9.4mm but I think it may be a little skinny. I'm pretty sure the 9.4mm dynamic rope I have is double rope. I'd probably feel better with single rope.
[1] http://upload.wikimedia.org/wikipedia/c ... ZyperY.jpg