Almost didn't read this updated thread - am glad I did. Whether Bob R's letter triggered the replacements or not - they seem to be an improvement. And the old signs were still in place when I was there on June 8th.
As has been noted many times before - if you're not paying attention, it's easier to walk down towards Guitar Lake than make the uphill turn to the right and continue on to the summit. I was a few feet behind someone on the 8th, and almost followed him down myself. He caught himself after about 20', turned back and we looked at each other sheepishly realizing we weren't paying attention.