I remember on our second trip to Yosemite we sat around the community campfire at Little Yosemite Valley campground and a group of other backpackers told us they were hiking Half Dome the next day. "Wait, but the cables are down...?" They told us that's the best time to hike half dome! No permits... no crowds... and the reality is, the cables aren't actually OFF Half Dome, they are just laying flat on the rock instead of at waist height.