NoCal has the same problems we do, unfortunately, according to an article I read last week out of El Dorado County. The one major difference is their more people lost up north, most likely because of we have more people on our trails keeping people with pictures of the message boards as map found.
Lasting solutions take thought and time. The location makes things difficult because there are not a lot of people there. What I would suggest to those who want something longer last is to contact the Inyo's Volunteer Coordinator and Recreation Officer. In the interim, pound into people's head that this is a dangerous area after dark, just like we pound into people's head that the chute should only be done by those with ice axe, crampons and basic snow skills. We do this in SoCal and people get hurt in the same places every year there doing the same things. However, it does get through to some. That is what this and Doug's board should be about.
Tangentially, after God knows how many news articles, clarion sirens blasting on the local news and eight new signs on Mt. Baldy. 5 people still got rescued on Mt. Baldy over the weekend...one seriously injured and one had a near death experience. Still Sunday night people wanted to use there brand new state of the art mountaineering gear to them...Microspikes, on this mountain for the first time. It you think a line of rock is going to make much of a difference above Mirror Lake, I got this bridge in San Pedro that needs selling.