I’m with Saratoga
My big horse is a great climber, less thrilled with long, steep downhills, so while I don’t get off a lot, on rides with long downhills, or if he seems tired, I get off and lead him down. Gives me a break too, and yeah, definitely for his joints, not speed!
Every time I get off to take a potty break, I also get to stroll, unless I pick the spot strategically, because Ned is well over 16h, and I need a stump or a rock or a ditch to get back on with any grace.
I remember at our first 50 (Elk Valley, PA, a VERY hilly ride) getting off and hiking up Big Charlie because it seemed Ned was going SOOOO slow. After about 1/2 mile of that, huffing and puffing, I hauled my chunky ass back up on him, patted him and told him he was doing just fine. Whatever pace he liked was fine with me.
My younger horse is a great up hill horse AND a great downhill horse. I don’t foresee getting off him much at all, tho like Bonnie said, I do try to be careful about downhill trotting, condition with it a LITTLE bit but not overdo it as I worry about the concussion on his joints.
Unlike my big horse, the young one just sits and boogies. I think he’s much easier on his own body going down hill than the big guy even with me on him. And moving along.
Your mileage may vary.