Hmm... Having raised my kids, I made it a point to say what I mean and mean what I say. That's not to say I never lied to them. For a short while they did believe in Santa Claus and the Tooth Fairy. I found no harm in that at all. In fact, as they grew older, they began to question those things and I gladly took them to a private room and let them in on an "adult" secret. Instead of being pissed about being lied to, they actually enjoyed the fact that the got a sneak peek into something their younger brother(s) didn't know...and they never ratted on me. LOL
In my personal opinion, there must be some sort of imagery into the fantastical. For example: When my youngest came home from school one day, he was like, "MOM! Did you know that we only use 10% of our brain?" (Well, I know that's not the complete truth, but he was excited about it and it was contagious. Then he asked, "What do you think we could accomplish if we used 100% of our brain?" I just shrugged with a big smile. "Maybe we could FLY." I wish I could capture the look of wonder on his face as he smiled back and hugged me. "Yeah...that would be cool."
But see, I never worried so much about fantasy and folklore because many of them are basically traditions passed down throughout the generations of my family.
But when it comes to saying what you mean and meaning what you say, I am very conscious about that!
When my kids were young, we'd be in the supermarket and I'd inevitably hear a mother screaming at her kids to put her coat on or she was going to throw it away. My kids and I would look at each other with knowing looks. "Do you think mama's gonna throw out the coat?" I would ask. "Nope," they'd answer. "That's why the kid's not listening."
By enforcing this policy with my kids, they have grown up knowing I'm a woman of my word. If I say yes, I mean it. If I say I'll be there, they know I'll kill myself to make it so. And in turn, I often get strange Skype messages from my kids introducing me to a bunch of their friends - or simply talking to me about anything - even when I sometimes have to remind them that I'm still their mother and don't need to know those things...ever. LOL
Now, my oldest son has Asperger's. He's 21 and will probably be living with me for a long time until he's comfortable taking the step toward independence like his younger brothers, so my policy on say what you mean really came from his need to rely on "truth" in me.
But let me be clear about something @williambanks - NO parent does it completely right. And NO parent does it completely wrong. To this day I have doubts about what I've done and how I've raised them. But I sleep better at night knowing that I've done the best that I could.
I have a feeling your daughter may find herself alienated a bit simply because she's frikken brilliant - and that bothers kids with less intellect. But there's no way you can dial it back for her. She will figure it out on her own. It's part of growing pains and balancing sense of self with public projection. That being said, IMHO, just be her solid go-to foundation when she has those bad days. Don't try and fix anything. Just be there with open arms and ears. She'll be fine. I know...because I was her once.