Okay, I would never ask a child not to be themselves, that's just backward thinking. However, I think it's okay to kids to develop coping skills in that they know what to say to who and when. I would never expect I five year old to know this, but as they get older.......
For example, on this forum we've discussed a variety of interesting and in depth topics. There is just a certain variety of "soccer mom" (for lack of a better term) I just wouldn't initiate a conversation on nuerology, psychology, etc. I have friends that I talk about with that stuff. And I have friends who I sit around with and discuss curtains, countertops and which clothing store the kids like best.
I like to have a lot of and variety of friends so that's a coping skill.
My DD came home and told me she was talking about her photograhic memory and she described in a very unusual way. It did not go over well with the second graders. Of course I didn't say anything negative about it.. it is just who she is. On the other hand, I'm pretty sure she was testing out how much of herself she can disclose and to who. I think she got her answer.