Picture from 11/23 - where I left the trail (trail on the right is darker on this site might try to lighten it):
And a screenshot of part of your map:
I think my photo is where your yellow route leaves the trail shown in blue(s) on the right and rejoins on the next switch back. I think I saw where the yellow left the trail again, but thought it was just a short connector to HWY 26, very close by, there is another marked trail down to 26 much further east.
I think I took a photo on my phone near here going up. I also took photo of the only really large Doug Fir, which also had a submerged fire pit, back further east, north of trail. Not worth sharing. Maybe your camp.
Allot to take in with all your info I would have guessed that they did not go on top of that one section sheer rock drop offs on south side (north of trail on the north where there are two trails) and maybe on both ends but did not check that out, your info says they did, so interesting.
I did wonder why they did not go down toward little zig-zag, but this last trip I think it might have been steeper than it looks, maybe that looked too narrow or muddy.
I did see a photo once of the hill after a fire, and thought how would anyone know where anything was!
It is good folks wanted to document this before that.
Oh do you know when they made the tunnel? At the time of building the Loop Hwy? Was it to preserve the wagon road, or just a hiking/horse path?
Lots of activity above the tunnel on power lines, and least more than I remember.
As far as chute 3 goes, back in 2009 I biked the loop road, I had planter faces[sp] and I forget now what it looks like right now but thought the chute from the loop hwy did look like a quarry. My recent time there though when I was looking for the campground I went to the top of the chute and said to myself this does look more like a chute. But I am no expert. Unless they exhausted all the rock in the quarry, it doesn't look like the one or two one sees along the Cloud Cap road. I don't know why this chute would be bare and the others have plants, maybe the amount of use, or it is a quarry, and the dirt left isn't as fertile. Or the continual erosion here is too much. The photo where he remarks about wire, does sound like maybe it isnt a chute , anyway, they did go down something like this, but it did not look like this when they did , that is why they would have abandoned it or they found something easier.
You really examined this! Thanks for sharing, and your photos do show the Tompkins diagrams I have been using, I had a few others but not nearly as easy to follow. But that doesn't mean they are correct.