Trebuchet wrote:
moss and oldtimer: Many thanks. Great recommendations! Let's see: Be consist, i.e. "no flip flops in trees" (good tree-climber wardrobe decision, too?); tailor your climbing _style_ to accommodate when you're tired; commit to safety and be responsible for maintaining safe habits and systems. Please correct me if I've misinterpreted either of you.

Having said all that, I believe that climb-rated (23kN+) screwgate carabiners, double-auto-locking carabiners, and stainless "screw_link_s" are secure.

I believe that still unanswered question is, "Can a screwgate carabiner be "properly closed" to adequately prevent un-threading and inadvertent opening?". No, say the pros.

Vibration, friction, shock. I believe all these types of forces should be considered as potential methods for thwarting a gate lock.

I think that something like the Tory Red Cap Finger Tips (http://www.toryinc.com/) might be adapted to reduce the tendency for the screwgate lock to un-thread. In fact, I'd say there might be a size that would be adequate to similarly reduce the ease with which some have said that they can thwart the double-auto-lock gate. I'll probably buy a handful, strictly for the ground-_base_d laboratory environment, and see what they'll do. OK, here's the disclaimer: This mere speculation on usefulness of a specific technology is in no way a recommendation to any climber to use any product referenced.

Thanks again.

You got it. If you're fatigued, stressed or in a crisis (rescue) situation you may accidentally attach to a screwgate and treat it like an autolocker. Imagine using your climbing system if you were sleep deprived for one night. Can you still use it smoothly and safely? Give yourself room for mental mistakes in your setup.

I don't like the idea of trying to "improve" the security of a screw gate. Added security may make it difficult to undo when you need to get off it fast (change over to SRT rappel during stinging insect attack). Using a screw gate means that you're aware that rope movement or branch contact could potentially unscrew the gate. Therefore you accept it and climb with that awareness to protect yourself.

It's well known that autlockers can also be opened by rope movement and branch contact. Again, the climber using an autolocker must be aware of this and pay attention during the climb.

A versatile climber can make use of either when they need to but why undermine yourself by mixing gate technology on purpose?
-moss