You can see rocks and structure during the day. Lee Wulff was innovative in all areas of fly fishing. Take his approach to casting, for example. He then described a technique he created to allow for longer casts with less of a back cast, especially with the shorter rods. He described an oval cast made by bringing the line from the water in a side-arm fashion and then raising the rod tip to a regular position as he made his overhead cast.
Nothing can survive scared half the time.
Trout need shelter to feel secure. . . . Let the fish relax. Be still and quiet so as not to scare him. If you understand fish, you can avoid having to cover a lot of water. The good fisherman is a good predator, just like a cat.