The crouch. The sneak. Staying low, moving slow. Using cover to your advantage. False casts away from the target. Paying attention to your relationship with the sun and the shadows that develop. Olive colored lines standard. Stealth camo clothes? Don't scoff. Talk to a Kiwi about camo sometime. Or a whitetail bow hunter for that matter.
This fly fishing gig should be treated as hunting. The approach can make or break the game. Thoughtful approaches equal opportunities.