Reminder to Use Large Diameter Carabiner With First Generation Trango Cinch

The Cinch User's Manual states: "Pear shaped locking carabiners are recommended."  This is a PSA that the first generation Trango Cinch has a potential defect that can result in the device not assisting the belay, and this is not the well-known and documented tendency for assisted braking device failure caused by a specific gripping action above the device on the climber's side of the rope - this problem involves the device being able to become stuck in a position of being fully open and allowing no assist to the belay.  Trango changed the design of the Cinch slightly at some point, so the newer ones do not have the same ability to fail with a smaller carabiner.  The device can only become stuck in the open position using a small diameter carabiner that allows the unit to rotate to a potential failure position.  Please use a large diameter carabiner with your Cinch just to be on the safe side.  I discovered this potential failure mode while investigating a climbing accident.  I am not at liberty to discuss details and am not claiming that the accident was due to this defect.  The likelihood of a Cinch failing with this failure mode with a small carabiner is very low, but is possible.  I have contacted Trango to give them the opportunity to be the ones to remind the community, but they made the choice to stay silent, based on their assessment of the low potential risk. The photographs may provide some explanation of the potential defect, but my purpose sharing this is to remind people using older models of the Cinch to use a large diameter carabiner.  The photograph of the red Cinch showing the two positions is for explanation only - the red Cinch's are newer and do not have this potential defect.  I have only seen this problem in the tan version of the Cinch, which has serial numbers that would indicate it is first generation, or an early iteration of the device.  

Where's the Vergo? Oh, wrong thread. :)

Oh, you mean this could happen?

And, with this interference there is not much assistance in braking, Vergo works like a tuber. I know - my climber took a fall, and, boy, was I surprised, or what.