Of course it would be best if the settings were so simple that no education were necessary. But my claim is (a) for a site like Facebook to work "well" [where

Of course it would be best if the settings were so simple that no education were necessary. But my claim is (a) for a site like Facebook to work "well" [where we can argue ad infinitum what "well" means], some information needs to be shared in the system, and some needs to be private. (b) this is often different for different groups of people. You now have to implement a privacy system that works for every piece of content, for every set of users that I want to define a setting for. I think you'll quickly come to something fairly complicated. There are very smart people trying to come up with abstractions and interfaces that make this easy to do, but I fear that at the end of the day, users are simply going to have to learn some new tricks if they don't want to be surprised. And that means, we have to figure out how to explain this complex system to them.