One thing that I've learned is that you can't just wait for someone else to lay down all the settings info. At some point you need to fill in some of those gaps yourself, and if settings are written in later on that contradict what you have already role played, then so be it.
There needs to be room for creativity on the part of players, and a willingness to be wrong about it at some point. If you don't take this risk, you end up with dull RP that's dictated by someone else. I'm not saying to write in aliens abducting krans or anything, but to go ahead and color in your rp with your own ideas and colors. The world will not end if you are somehow wrong or are in conflict.
This thing about needing a settings person to tell you what a goddamn gem should taste like is a bit too conservative for me.
Like I said, they taste like Skittles and make you fat and dumb.