I have no proof of this, nor have I even heard it through the grapevine, but I absolutely could see Tess Darby sitting down with Kellie and saying, "Coach, I think we need more quickness on the floor, and it makes the most sense to give a lot of my minutes to a quicker player."
NOT that Kellie would need a player's suggestion/permission to make that decision, but I'm saying this because my gut tells me Tess Darby wants her team to win and get to the NCAA Tournament more than Tess Darby needs herself to be on the floor. She's a bright girl, and she has eyes, so if she thinks someone else needs to take her place if only for the slightest improvement, she will gladly accept a lesser role.
That young woman is all Lady Vol, and for her entire life.