The problem is that we are using cache. Ideally we should use cache as much as possible as this helps speed things up. If we have to look for who posted last we may as well grab all of the new posts. Then there is no point to caching this information.
I will look into displaying "last post by" when the option "force public" is not used since we wont be caching any information. This of course will be an option. This isn't something that will be high on my list of to do's though. I have a ton of things I'm trying to blend and smooth out... lol
So this "last post by" is for the news section?