You can always sleep after the hike is over. Getting on the trail at 3 or 4 in the morning sounds extreme, but it really makes sense. High altitude hikes can be prone to afternoon thunderstorms. It's much better to reach the summit by 10-11am and be well on the way back down during vulnerable afternoon hours. Another benefit of heading out at or before dawn is cooler weather.
Less heat means less sweating, therefore less water needed and a lighter load.
Hiking on a trail at night during a full moon is an adventure everyone should experience. A flashlight is hardly needed. A minimalist approach is suggested to food, clothing, and other items. Each hike should be planned considering the risks involved. One advantage to extreme day hiking on well-established trails is the reduced need for survival items since its harder to get lost or hurt yourself.