23 to 24 looks similarly hard unless you spot the stone wall on the map. If you do it's trivial.
Your description of 20 sounds like exactly what happened to me, except that I slowed down on the trail to relocate and found the sharp bend a few contours above those cliffs. I was following a reentrant down the hill but evidently not the one I had wanted.
Congrats on nailing 10. Those parallel lines of small cliffs were a great setup for a parallel error.