"On Rope" seems to me to be a fantastic book. It really stands out with a fresh vibrancy from the raw enthusiasm and vast accumulated knowledge poured into it. This is as best as I can judge - I have never gone caving or rock-climbing.
This book is all about rope techniques where there is a person on the end of the rope which is often very long. This is the world of high-specification braided rope (specifically, "kernmantle") and careful techniques.
My rope use has been rigging in construction, moving steels - different.
But still find it full of goodies. For instance - when someone was repairing a webbing strap, showed the sketches of which stitch pattern gives the highest strength. That's from the "On Rope" section on harnesses. So still useful to have. And inspiring.