It sounds like you’re storing the potatoes exactly right. Even in the best of storage conditions, potatoes will eventually sprout. If allowed to continue as-is, the sprouts will grow and draw upon the moisture content of the potato. Not unlike cut flowers will draw water from a vase to stay hydrated. By removing the sprouts now, this will nip this in the bud, so to speak, and the potato will not dehydrate nearly as quickly. So yes, by removing the sprouts and continuing to store the potatoes away from light, unwashed and in the 48°F area you will be able to optimize the potato storage period. But don’t wait too long. Prepare and enjoy those wonderful Idaho potatoes tonight! (We’ll grow more).