The first time I fished with Bud Rowland, his son Brandon, who was a teenager at the time, came along. When Brandon casted from the bow for the first time, I was amazed at his cast. In particular, his double haul backcast was a thing of beauty. It was powerful, long and accurate. And it wasn't in my repertoire, even though I was an FFF-certified casting instructor.
My friend Skipper Ray also had this ability. What I have found in the years since is that the backcast is an essential component of a saltwater angler's skill set, and it's not something that will develop without effort.
Nature is the best teacher, I often say. When you get on the flat, and you're casting in the wind, you can't simply use your forehand cast to reach targets in every direction. So what do you do? At first, you turn, and you try to "chuck and duck" on the wrong side of the wind, and you get nailed in the back by your fly. Then, having learned that lesson, you begin adjusting to the demands of the moment by making a sloppy backcast that falls short. And you miss the opportunity.
Most people use their backcast in a pinch, and they are punished for their lack of practice. Since taking the Rowlands fishing with me back in 2000, I have developed my backcast to the point when I would rather use my double haul backcast in the wind than my forehand cast. I can cast further, and more accurately with my backcast, and because of that I am always set up to cast with my backhand as I wade or cast from the boat.
In flyfishing, the backhand cast, especially in the wind is the more powerful and distant stroke. Why? Because when you lift your line out of the water, and power it behind you into a 15-20 mph wind, it takes a lot of strength and rod speed to drive the line into the wind. The forehand cast is the stronger one to use to power the line into the wind. By comparison, the downwind cast requires relatively little strength to execute, and the backhand cast offers plenty of strength to accomplish the downwind cast. So turn to your left if you're right handed, and cast firmly into the wind. Add to that a water haul on the lift out, and then add a second haul on the downwind stroke, and your cast should go further, and more accurately with practice.
I will post a video soon that breaks down the mechanics of the double haul backhand cast. In the meantime, you can take your body to the threshold of this skill, simply by practicing a more primitive version of the backhand cast. Turn to the left if your right handed, and cast into the wind with your more powerful stroke. See if you can get the line behind you, and then drop the line downwind on your backcast. This primitive backhand stroke with serve the need in a pinch, but in time you will find that if you do a single haul on your back stroke by crossing your hands as you cast, your two arms will work together to develop sufficient line speed without as much pivot. So when you power the line into the wind, take your left hand and move it under and across your lower body in the opposite direction, and you will achieve the single haul on the back stroke. Then, as you cast forward, simply uncross your arms, and you will achieve the forward haul. I realize these words need some video support, but see what you can do until Ryan and I post a video on this method. The time to practice is before you encounter the fish.