Board Thread:Episode Discussion/@comment-34633327-20180120015359/@comment-27121183-20180121012441

I took Yang not telling as more of a silent thank you for Raven giving up the relic, as well as a mod to Yang truly questioning things now. As for her not being needed, the way she kicked Cinders ass would be a good reason to keep around a maiden, relic or no relic. There's still a chance Salem could recruit another maiden or steal their powers, etc.

It was also a good way for Yang not to burn that bridge with her mom, which I think shows how far she's come in maintaining her temper. Maybe she's realized why her eyes change the way they do when she's angry, from Taiyang calm to Raven furious.