What is a potential result of overmixing a high fat cake batter?

Overmixing a high fat cake batter can lead to a dense texture because it develops the gluten in the flour more than is desirable in a cake. Cakes are generally meant to be tender and light, and excessive mixing causes the gluten strands to become too strong, interfering with the cake's ability to rise properly and resulting in a heavy, compact crumb rather than a light and airy one.

While it’s true that a high fat cake relies on a careful balance of ingredients and mixing time, the focus here is on how the gluten development affects the final texture. In contrast, too much rise is typically caused by other factors, such as overreliance on leavening agents, and would not be a direct consequence of overmixing. An underbaked center usually relates to baking time or temperature rather than the mixing process itself. Lastly, a dry crumb may result from overbaking or insufficient fat or moisture in the batter, not purely from overmixing.