I've approached a few guys. One said no that his knees couldn't do it, another said yes then canceled due to work, some said maybe. Finally, one guy committed.
This trip is rated 9 out of 10 for difficulty. Part of the problem is water availability which is why I decided on a trip in March rather than a hot, dry month. It's a route that doesn't follow a developed or maintained trail for the entire loop so route finding is a concern. Two or three years ago an experienced couple from Salt Lake City got lost for a few days on this route and had rescue teams searching for them. There's a 20 feet repel along the way. But, the main concern is "the ledge". Everyone is concerned about the ledge and the 40 feet drop.
Here's the pertinent portion of the National Park Service's description of the route.
Just before the eastern arm joins the main stem of the drainage hikers are presented with an impassable pouroff. This obstacle can be circumvented on either side but it's safer on the right (north). Follow a series of ledges along the north side of the canyon to a talus slope and descend to the bed of the drainage below the fall. If you chose to bypass the pouroff on the left side prepare for a thrilling traverse along an exposed ledge only a few inches wide. Both bypasses are cairned at the top and bottom of the pouroff so choose wisely.I've searched the web for trip reports and photos. I've found only 12 photos of the ledge and two of the alternate route. It appears the adjective "thrilling" is appropriate. In one trip report a guy crossed the ledge then realized he had left a camera strap so he had to cross back to retrieve it. Triple the thrill!
In the collage below the ledge is marked in red. Photo 13 (see the large version) shows the alternate route being taken by the man in the bottom of the photo while a friend watches from above.
I read trip reports by two men who had hiked every developed trail on the south side of the canyon. They saved this trip for last. Both said it was the best of all hiking they did in the Grand Canyon.
The friend who committed to making the trip did so with a disclaimer: only if we take the alternate route. I'll drive to the canyon on November 1 to get the permit for next March. Four and a half more months of anticipation.
Ledge collage. (Larger version: 1383 x 1938 pixels)