So the picture was taken while southbound on the Davis Path, it was on my left. It was in the same place on September 1. Some other people walked right by it that day.
There is another sign, the white with green lettering large rectangular AMC/FS contraption, almost right across the trail from it on the right, perhaps a few feet north. It was about eye level and positioned so as to be parallel to the trail on the moss covered rock face. It told the distances to other points of interest, which I can't remember now. (probably Mt Davis and Boott Spur)
Another item of mild interest, in regard to my first post on this thread, the area with the campsites just before where the Isolation trail meets the Davis path (as you go uphill, ie on the way in) is much less confusing than it was 3 years ago. Much less in the way of herd paths, and new FS camping signs as well. The yellow blazes (mentioned in 27th ed of WMG) have pretty much faded away. I think we saw 2 or 3 very faint ones on the far end.
While we're on the subject, what's the deal with the "Entering the Alpine Zone" sign that's partway up the spur? If it's not an official trail, why is it there?