Going Down…
Didn’t have time to read all the replies.
I ride in pretty mountainous country all year round, pretty much if you aint’ going up, you are going down (Interior B.C.)
We deal with a lot of loose slippery slopages and some pretty much straight down ups at times, due to the clay/granite/shale crap that goes for footing around here.
I will always let a horse pick it’s way down as a rule, unless I’m riding a stupid horse who can’t figure out where to walk, then I’ll direct (most of my horses learn this skill pretty quickly though)
I tend to lean slightly… just slightly back, nothing major, a small shift in weight that frees up the horses shoulder.
I will go crossways across a hill if its safe footing, otherwise it’s straight down.
By the by, a horse can fall backwards going down a steep hill, I had a horse do it. He ended up sitting on his rump pretty much is all, but he definitely fell.
Think of us walking down a steep section, when we fall, do we fall forwards or on our butt if our feet slip out from under us? (Both - depending on where our balance is at that moment)