I'm sure you can chime in here, but I have read that Losi keyed in the CF plates so it won't tweek.
I could see how it would help to keep things from shifting, but don't the carbon fibers contribute to tweeking. It's the twisting motion from a collision that makes it weaken over time. From my expirence it does not take a long time for this to happen. I'm sure a tub chassis would be less prone to this.
