Its not the specific answer I have an issue with, it's how it is being used. It's a dues ex machina or whatever. I can accept that last scene with her in the RoD when T and V's keyblades come to save her - as I can see her friendship with terra and ven also gave her a strong connection with their keyblades, as they are sentient. What I don't get is she used this power somehow. It's not like they actually helped her. They were both occupied. Even their hearts were busy with a struggle.
Well, considering Xehanort was using a new body, and Terra was resisting, Terranort was taken down a notch in terms of power. I have a feeling we will be facing a true Terranort in KH3.