Here's a pic of a climber wearing a New Tribe saddle using a rope bag as a weight to tail the static line thru the ascenders during ascent of the Yosemite Sequoia.
Sorry, the correct day for the tree climbing competition on ABC's Good Morning America is Thursday, Nov. 14 (not Wednesday the 14th, as was previously reported)
This discussion about SRT needs to take into account that SRT is often new to the folks who mainly use doubled rope technique. The basics are really important, especially when trying new stuff. Here's a link to some of the basics of DRT:
Climbers Bag of Tricks
Specifically referring to the lockoff holes to block the cam on an ascender with a spare biner, these don't really qualify as a redundant backup. The Mar-bar is sold in catalogs & often used without the required second point of attachment to the harness.
One place where this can really be a problem is with the Pantin footcam. I haven't seen a situation where a biner should be inserted into this lockoff. Sideways movements are what usually permit the line to escape from this device. I'd like to hear more feedback on this gadget. It is gathering greater acceptance from tree climbers.
From a safety standpoint, a climber runs the risk of a heel hang if the Pantin is locked off. Of course, noone expects their upper ascenders to come unattached, tipping them upside down. But if this miraculous turn of events were to occur, the climber would be good & stuck. A heel hang is a potentially fatal position. We had a climber get excited when encountering a bee's nest and drop back with his heel in a tight fork. We're talking helpless.
Besides the Pantin, make sure at least two other points of attachment exist between you and the jug line. A prussik cord mounted just above the upper ascender, and running down to the hip dee is a nice way to go. The ascender shoves it on up ahead of itself with no tending needed by the climber.
This setup with a prussik cord up top works great as a backup when descending with a figure 8 or bobbin descender, such as a Petzl Stop, Kong Speleo, Anthron, etc.
My latest favorite descender backup is another descender, mounted just above the first one on an 8-10" tether to the hip dee. I love the control of a figure 8 daisychained above the Stop. This worked great on that skinny Spiderline, and is the cats meow in slippery, wet weather.
To keep from melting the rope, follow the instructions stamped on the side of the Stop that limit the rate of descent to 2 meters per second. They're not kidding. That is slow, and one must also come to a complete stop every 50' or so to keep things cool. When you can smell it melting, it's past time to slow your descent. Climbing etiquette dictates that abseiling on borrowed rope will be done at a slow rate, as a courtesy to the person that loaned out the descent line.
You can adjust rope handling chareristics for different diameters, as well. The newer polyester static lines have more stretch and subsequent dynamic loading properties, and have a higher melting temperature. Other statics have a smoother surface because they are braided on machines with more (48!) carriers.
These modern days bring to the table all of these factors (and a whole bunch more!) that climbers must take into account. Not only do we have to learn the basics, we must also learn the subtleties. As the manufacturers respond to changing market demands, they incorporate new technology. Our days of relying on the status quo are long gone !