I’m going to leave aside the tools, or the execution. I’m simply going to do some math for folks who might be interested.
he weighs 180lbs.
If he’s standing in the top step of that aider, and has not repositioned his tether anchor, and he falls, he’s falling roughly 54”. His tether is roughly 60” long from anchor to his tie in.
This would result in a fall factor of 1.92, with 17.6kn of force placed on his tether anchor, and the connection to him.
he appears to be using a spliced tether, so no loss for knots there. That rope is likely rated at least to 24kn - good there.
amsteel bridge - good there, based on limited testing by saddle suppliers. I’m not comfortable, but let’s call it good.
bridge loops - probably good.
carabiners - probably good.
prussic - 6mmaccessory cord rated at 12-18kn................
conservatively, if his prussic holds, hell only break His back in 2-3 places. If he’s at 20’ when his prussic breaks, hell probably only break it in one, and then multiple broken bones when he hits the ground.
I’ll offer two pieces of advice here:
If your tether is not tied directly to your saddle, and you’re just using your prussic to protect you, you’re doing it wrong.
a 36” fall on a 60” tether made of static rope will likely mean a life changing injury for most people who frequent this forum. For some of our bigger members, it may only take a 20-24” fall.
be safe folks