Thought I’d share this reply on the subject of rescue scenarios that are outside of the norm (I’ll do a full response on my blog later, as it’s a really interesting topic).
“Hi James, I might be able to write a longer reply (just packing), but a lot of the scenarios are ideal, and in reality, things tend to be far from it, as you tend not to have all the gear you need (no prusik!), or the right kind of belay, the belay itself is designed for a factor 2 (equalised to the belayer), not a static upward pull (as you’ve identified). What you really need is to learn and understand, fully, a set of knots and techniques and then be able to apply them to a wide range of imperfect situations (there will not be an ideal rescue).
Personally, I always use a cordelette in a standard set up, and have two prusik loops, a rescue cord (4m of 6mm), and maybe a spare cordelette, and will work with what I have. 90% of the time the person at the other end is going to have to save themselves, and that’s something worth really training for (going down the wall or hanging off trees), and for that 10% you might be best calling for help, as doing a self-rescue could be more dangerous (people who do wilderness medicine always want to sew someone up, or stick an IV in their arm, when really just pressing HELP is the best option), so don’t get sucked into being a superhero.
As I said, it’s a great idea to spend a day at a wall just practising different scenarios, getting someone hanging on the rope and taking away the gear they need (take away all their Prusiks and tell them to get out of that!). Hope that at least gives you an idea that it’s best not to worry about things that are beyond your control, but focus instead on learning how to deal with things beyond your control!