What, exactly, is the point of hydrating batters?

Resting pancake and crepe batter allows the flour's starch granules to absorb liquid, softening them. This hydration process makes pancakes and crepes more tender and potentially lighter. For leavened batters using baking powder, add it just before cooking to preserve its leavening power. Resting a batter before adding baking powder prevents premature release of gases. The increased hydration during resting also encourages gluten formation. Gluten development can toughen pancakes and crepes, which is undesired. No-knead bread recipes benefit from slow gas bubble activity, fostering gluten. In pancake and crepe batters, gluten isn't usually desired because it leads to a tougher texture. Resting might slightly promote gluten formation, counteracting the desired tenderness. Therefore, the resting time and baking powder additions should be considered carefully. The effects of resting on the final product depend on the specific formulation and desired outcome.