True. But that's why Emma should never say Rachel will never be her equal. Rachel is Jean's daughter and her power SHOULD BE off the charts. Emma was no match for Jean. With training and experience Rachel should be able to beat her.
And to be honest, I always understood Rachel's anger here. I wish there was still at least one prominent X-Man who didn't trust Emma (not counting the Cabal nonsense) because even if no one expects Emma to go all EVIL again, the stuff with her and Scott and Jean was not cool and was wrong. Scott, tool that he is, got all emo about it, but Emma didn't even bother to play guilty. Right or wrong, Rachel's anger at Emma is understandable (I wish it had continued too).