It was exceedingly steep
There's really no way you could have anticipated that.
Here's an email exchange that shines a brighter light on it. Here I am, asking the organizer about the trek:
Thanks for the invitation, John.
I like the idea, but I need to think about it pretty seriously. I'm 74 and will be looking at 75 just after the trip. I don't want to be a hindrance. I'm pretty sure I can handle the walking and altitude. But if there's much climbing, well, my balance has gone all to hell. If there is something like a rock slide we have to climb over, I could do it. But if there is a lot of stuff like that, ---- or if it's mostly like that --- then it would be a problem for me.
And here's his reply:
From what I know, this is all on well-graded trails.
Dunno how much walking you've done in this part of the world, but the trails are essentially the interstate highway system -- they're how all goods, from harvested apples to billiard tables, move in this region, either on the backs of humans, yaks or horses. So the trails tend to be smooth and gently angled. That's not to say there couldn't be a landslide blocking the trail, but in 10 previous Himalayan treks I've never encountered one.
And here's what happened:
Our guide, Jamling Norgay (the son of Tensing Norgay), had his own trails avoiding the new Jeep road to Lo Mothang. The jeep road is well graded, but to avoid it, you are on other trails which are, as I say, exceedingly steep. Given my info before the trip, yeah, there was no way I could have predicted this.